Substrate treating method, substrate-processing apparatus, developing method, method of manufacturing a semiconductor device, and method of cleaning a developing solution nozzle

ABSTRACT

There is disclosed a developing method of developing a photo-sensitive resist film in which a desired pattern is exposed, including subjecting the exposed photosensitive resist film to a first developing treatment; supplying a cleaning solution having an oxidizing property or alkalinity with respect to the surface of the resist film to the photosensitive resist film subject to the first developing treatment to perform a first cleaning treatment; subjecting the photosensitive resist film subjected to the first cleaning treatment to a second developing treatment; and subjecting the photosensitive resist film subjected to the second developing treatment to a second cleaning treatment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a division of application Ser. No. 10/988,639, filed Nov. 16,2004, which is a division of application Ser. No. 10/351,422, filed Jan.27, 2003, which are incorporated in their entirety herein by reference.This application is also based upon and claims priority from priorJapanese Patent Application Nos. 2002-17937, filed January 28, 2002, and2002-57764, filed Mar. 4, 2002, the entire contents of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a substrate treating method andsubstrate treating apparatus in which a treating solution is used totreat a substrate and which are particularly for use in performing acleaning treatment subsequently to a developing treatment in a processof manufacturing a semiconductor device.

2. Description of the Related Art

When a semiconductor device, liquid crystal display device, andelectronic circuit component are manufactured, a substrate is subjectedto a developing treatment and thereafter successively subjected tocleaning and drying treatments so as to form a pattern in a process offorming a circuit including a device, wiring, and the like.

A manufacturing process of the semiconductor device first comprises:forming a film to be processed (e.g., an insulating film, conductivefilm for wiring), and a photosensitive photo resist film on asemiconductor substrate in a known method. Thereafter, this photo resistfilm is subjected to the developing treatment. Here, as well known,after a predetermined pattern is projected/exposed in the photosensitivephoto resist film on the semiconductor substrate via a reticle forexposure, a developing solution is supplied to form the pattern.

After the developing treatment is performed, the developing solution, adissolution product generated during the developing treatment, and microparticles remain on the surface of the semiconductor substrate. Whenso-called impurities and contaminants are left in this manner, in aprocess of using the pattern of the photo resist as a mask to subjectthe film to be processed (e.g., the insulating film, conductive filmforming a material of a wiring layer) to etching processing, an error ofdimension is generated, and yield drops in the manufacturing of thesemiconductor device.

Therefore, it is necessary to successively perform the cleaning anddrying treatments, bring the surface of the semiconductor substrate intoa clean state, and remove the remaining developing solution, dissolutionproduct generated during the developing treatment, and micro particles.

A related-art cleaning method comprises: rotating the substrate at ahigh speed; discharging the cleaning solution via a fixed nozzle;passing the cleaning solution toward a peripheral edge from a middleportion; and replacing the developing solution with the cleaningsolution to stop the progress of development reaction. Moreover, themethod further comprises: washing away and removing the developingsolution, dissolution product generated during the developing treatment,and micro particles from the substrate.

In recent years, technical developments such as miniaturization and highintegration of the semiconductor device and bore diameter enlargement ofthe semiconductor substrate have been performed. When the bore diameterof the semiconductor substrate is enlarged, that is, when an area of thesubstrate increases, many problems are generated in using therelated-art cleaning method.

A discharge port of the nozzle is disposed and fixed in a position abovethe middle portion of the semiconductor substrate. Therefore, a degreeof replacement of the developing solution increases in the middleportion directly contacting the cleaning solution discharged from thenozzle and in the vicinity of the portion on the semiconductorsubstrate, the dissolution products and micro particles are alsoeffectively removed, and a cleaning effect is enhanced.

However, the peripheral edge of the semiconductor substrate is notdirectly hit by the cleaning solution with a sufficient pressure, and islow in the cleaning effect as compared with the middle portion of thesemiconductor substrate and the vicinity of the portion. Therefore, inthe peripheral edge of the semiconductor substrate, a part of thedeveloping solution remains without being replaced, the dissolutionproducts and micro particles are not completely removed and remain, andso-called cleaning spots are generated.

Moreover, in the related-art cleaning method including the dryingtreatment, the substrate is rotated at a high speed. Therefore, with theenlargement of the bore diameter of the substrate, a physical load isfurther added, and the pattern of the photo resist formed by thedeveloping treatment is adversely influenced.

For example, when the substrate having a large bore diameter of 300 mmor more is used to manufacture the semiconductor device, the peripheraledge of the semiconductor substrate is influenced by a centrifugal forceand cleaning solution flow. A phenomenon remarkably occurs in which thepattern of the photo resist formed by the developing treatment isdamaged or pattern falling is generated. Thereby, it is necessary toperform the cleaning and drying treatments without rotating thesubstrate after the developing treatment.

With the miniaturization of the dimension of the semiconductor device,the developing solution does not sufficiently permeate between thepatterns in a related-art developing method, and thereforenon-uniformity of a local pattern dimension in a chip raises a problem.Moreover, with the bore diameter enlargement of the substrate, in therelated-art developing method, the non-uniformity of the patterndimension in a substrate plane is caused, and a large problem occurs.

Additionally, in general, alkaline aqueous solutions such astetramethylammonium hydroxide (TMAH) are used as the developing solutionof the photosensitive resist in the manufacturing process of asemiconductor. Since the developing solution is an aqueous solution,wettability to the photosensitive resist surface having a hydrophobicnature is not sufficient. Therefore, when a reaction product generatedas a result of neutralization reaction is in the vicinity of thesurface, the developing solution is not easily diffused between thereaction product and photosensitive resist surface, and alkali ionconcentration locally differs. As a result, it has been observed that adeveloping rate differs with a position.

For example, there are a pattern disposed in a broad dissolution regionand a pattern disposed in a region whose periphery is hardly dissolved.In this case, for the pattern disposed in the broad dissolution region,an amount of reaction products present in the vicinity of the pattern islarge, the developing solution is not easily diffused between thereaction product and photosensitive resist, and the progress of thedevelopment is inhibited. There is a problem a line dimension becomeslarge (dimensional difference of a coarse/dense pattern) as comparedwith the pattern disposed in the region whose periphery is hardlydissolved.

BRIEF SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided asubstrate treating method comprising: supplying a treating solution ontoa substrate; and continuously discharging a first cleaning solution tothe substrate from a first discharge region disposed in a nozzle whilemoving the nozzle and substrate with respect to each other in onedirection, wherein a length of a direction crossing at right angles tothe direction of the first discharge region is equal to or more than amaximum diameter or longest side of the substrate, the nozzlecontinuously spouts a first gas to the substrate from a first jetregion, and the length of a direction crossing at right angles to thedirection of the first jet region is equal to or more than the maximumdiameter or longest side of the substrate.

According to another aspect of the present invention, there is provideda substrate treating apparatus comprising: a substrate support portionwhich supports and fixes a substrate; a nozzle including a firstdischarge region in which a first solution is discharged to thesubstrate and a first jet region in which a first gas is spouted to thesubstrate; and moving means for relatively moving the nozzle withrespect to the substrate in a direction substantially parallel to a mainsurface of the substrate, wherein a width of a direction crossing atright angles to a relative movement direction of the first dischargeregion and first jet region is equal to or more than a maximum diameteror longest side of the substrate.

According to another aspect of the present invention, there is provideda developing method of developing a photosensitive resist film in whicha desired pattern is exposed, comprising: subjecting the exposedphotosensitive resist film to a first developing treatment; supplying acleaning solution having an oxidizing property or alkalinity withrespect to the surface of the resist film to the photosensitive resistfilm subjected to the first developing treatment to perform a firstcleaning treatment; subjecting the photosensitive resist film subjectedto the first cleaning treatment to a second developing treatment; andsubjecting the photosensitive resist film subjected to the seconddeveloping treatment to a second cleaning treatment.

According to another aspect of the present invention, there is provideda developing method of developing a photosensitive resist film in whicha desired pattern is exposed, comprising: supplying a developingsolution to the photosensitive resist film; and fluidizing thedeveloping solution on the photo-sensitive resist film, wherein the stepof fluidizing the developing solution includes an off time for which thedeveloping solution reaches a bottom surface of a region of thephotosensitive resist film soluble to the developing solution between astart time and end time.

According to another aspect of the present invention, there is provideda developing method of developing a photosensitive resist film in whicha desired pattern is exposed, comprising: supplying a developingsolution onto the photosensitive resist film; and fluidizing thedeveloping solution on the photosensitive resist film, wherein a starttime to fluidize the developing solution is after an off time for whichthe developing solution reaches a bottom surface of a region of thephotosensitive resist film soluble to the developing solution.

According to another aspect of the present invention, there is provideda cleaning method of a developing solution supply nozzle for use indeveloping an exposed photosensitive resist film, comprising: supplyinga developing solution to the developing solution supply nozzle; andsupplying an oxidizing solution to the developing solution supply nozzlewhich supplies the developing solution onto a substrate to clean thenozzle.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a whole diagram showing a treating mechanism of a substrateaccording to a first embodiment;

FIG. 2 is a plan view showing a constitution of a nozzle for a cleaningtreatment according to the first embodiment;

FIGS. 3A, 3B are sectional views showing a substrate treating methodaccording to the first embodiment;

FIG. 4 is a sectional view showing a substrate treating method accordingto the first embodiment;

FIGS. 5A, 5B are diagrams showing an effect of the first embodiment;

FIG. 6 is a whole diagram showing a treating mechanism of a substrateaccording to a second embodiment;

FIG. 7 is a plan view showing a constitution of the nozzle for thecleaning treatment according to the second embodiment;

FIG. 8 is a sectional view showing the substrate treating methodaccording to the second embodiment;

FIGS. 9A, 9B are diagrams showing the effect of the second embodiment;

FIG. 10 is a sectional view showing the substrate treating methodaccording to the second embodiment;

FIG. 11 is a diagram showing a flowchart of a treating procedure of adeveloping treatment method according to a third embodiment;

FIG. 12 is a process diagram showing the developing treatment methodaccording to the third embodiment;

FIGS. 13A, 13B are process diagrams showing the developing treatmentmethod according to the third embodiment;

FIGS. 14A, 14B are process diagrams showing the developing treatmentmethod according to the third embodiment;

FIGS. 15A, 15B are process diagrams showing the developing treatmentmethod according to the third embodiment;

FIGS. 16A, 16B are process diagrams showing the developing treatmentmethod according to the third embodiment;

FIG. 17 is a diagram schematically showing a graph of a reflected lightintensity from a conventional substrate obtained during observation ofcondition of dissolution by a developing solution of KrF positive typeresist.

FIGS. 18A, 18B are sectional views schematically showing a resist filmbeing developed;

FIG. 19 is a diagram showing a flowchart of a developing treatmentprocedure according to a fourth embodiment;

FIG. 20 is a diagram showing a schematic constitution of a developingtreatment apparatus according to a fifth embodiment;

FIG. 21 is a diagram showing a flowchart of the developing treatmentaccording to a sixth embodiment;

FIG. 22 is a process diagram showing the developing treatment accordingto the sixth embodiment;

FIG. 23 is a diagram showing a reflected light intensity change from theresist film being developed;

FIG. 24 is a diagram showing a flow of developing start, developingsolution flow, and developing end along a time axis;

FIG. 25 is a diagram showing a relation between timing and dispersion ofsolution flow;

FIG. 26 is a diagram showing the reflected light intensity change fromthe resist film being developed;

FIG. 27 is a diagram showing a relation between the timing anddispersion of the solution flow;

FIG. 28 is a diagram showing a flowchart of the developing treatmentaccording to a seventh embodiment;

FIG. 29 is a diagram showing a schematic constitution of the developingtreatment apparatus according to the seventh embodiment;

FIG. 30 is a plan view showing a constitution of a nozzle for treatingthe substrate according to the first embodiment; and

FIG. 31 is a plan view showing the constitution of the nozzle fortreating the substrate according to the second embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described hereinafter withreference to the drawings.

First Embodiment

In the present embodiment, a developing treatment, cleaning treatment,and drying treatment are performed so as to form a pattern having apredetermined dimension and shape in a region to be treated on asubstrate. Moreover, in the present embodiment, a developing treatmentapparatus of a so-called single wafer process system is used which cancontinuously perform processes of the developing, developing, and dryingtreatments in one substrate in one apparatus.

A treatment unit which can continuously perform the developing,cleaning, and drying treatments with respect to the substrate isdisposed in the developing treatment apparatus. In the presentembodiment, each corresponding treating mechanism is used to perform aseries of processes of the developing, cleaning, and drying treatmentsin this treating unit.

As one example, a developing treatment mechanism is disposed to performa known scan developing treatment in this treating unit. In a part ofthis developing treatment mechanism, a movable nozzle for developing isdisposed which can move in vertical and horizontal directions so as todischarge a developing solution (treating solution) and scan on thesubstrate. In this nozzle for developing, an elongated rectangularslit-shaped discharge port is disposed to supply the developing solutionto the region to be treated on the substrate by a uniform amount.

Moreover, in addition to the above-described constitution, as shown inFIG. 1, the treating unit also includes a cleaning treatment mechanism.A constitution and operation of the cleaning treatment mechanismdisposed in the treating unit which performs the developing, cleaning,and drying treatments will be described hereinafter in detail withreference to FIG. 1.

It is to be noted that FIG. 1 shows a main constituting part related toa cleaning treatment mechanism 100.

The unit for performing the developing and cleaning treatments includesthe cleaning treatment mechanism 100 shown in FIG. 1. The cleaningtreatment mechanism 100 includes main constituting components of a chuckfor fixing/supporting 101, nozzle for cleaning 102, and scan mechanism111. The chuck for fixing/ supporting 101 and nozzle for cleaning 102can relatively move the nozzle 102 with respect to the substrate, whenthe scan mechanism 111 moves the nozzle 102.

In the cleaning treatment mechanism 100, after the developing treatmentis performed, a substrate 103 is laid and fixed onto the chuck forfixing/supporting 101, a predetermined cleaning solution is suppliedfrom the nozzle for cleaning 102, and the surface of the substrate 103is subjected to the cleaning treatment. It is to be noted that thesubstrate 103 has a diameter of about 300 mm in one example.

In the present embodiment, as described above, the nozzle for cleaning102 of a movable type is used. Concretely, the nozzle for cleaning 102can move substantially in parallel with the surface of the substrate103. Moreover, as one example, the nozzle for cleaning 102 isconstituted of three nozzles 102 a, 102 b, 102 c.

In the present embodiment, as shown in FIG. 2, the nozzle for cleaning102 is constituted by disposing three nozzles 102 a to 102 c adjacent toone another and integrally combining the nozzles.

In the present embodiment, the nozzles 102 a, 102 c discharge thecleaning solution to the substrate 103. Moreover, the nozzle 102 bspouts air with a high pressure to the substrate 103. It is to be notedthat the nozzles 102 a to 102 c can independently be operated todischarge or spout the cleaning solution or high-pressure air.

Here, the nozzles for cleaning 102 are disposed opposite to one anotherin order of the cleaning solution supply nozzle 102 a, air supply nozzle102 b, cleaning solution supply nozzle 102 c in a scan direction.

Moreover, as shown in FIG. 2, the respective nozzles 102 a to 102 c areformed in elongated rectangular shapes, and a large number of cleaningsolution discharge ports 104 for discharging the cleaning solution and ajet port for air 105 are formed in bottom surfaces of the nozzlesdisposed opposite to the substrate 103. Here, the respective cleaningsolution supply nozzles 102 a, 102 c are disposed in two rows inparallel with each other.

Furthermore, a large number of circular discharge ports 104 are arrangedin the bottom surfaces of the respective cleaning solution supplynozzles 102 a, 102 c. Here, the discharge ports 104 are formed incircular shapes, and can discharge each cleaning solution to the outsidewith the high pressure. Additionally, the discharge ports 104 arealternately arranged in two rows in the respective cleaning solutionsupply nozzles 102 a, 102 c so as to form the rows extending in parallelwith each other. A region of the cleaning solution supply nozzle 102 ain which a plurality of discharge ports 104 are arranged is a firstdischarge region. A region of the cleaning solution supply nozzle 102 cin which a plurality of discharge ports 104 are arranged is a seconddischarge region.

In a process of performing the cleaning treatment, the predeterminedcleaning solution is discharged via the cleaning solution dischargeports 104. Each of the cleaning solution supply nozzles 102 a, 102 c canuniformly supply a predetermined cleaning solution to the region to betreated on the substrate 103 in a direction vertical to the scandirection. At this time, as described above, the respective cleaningsolution supply nozzles 102 a, 102 c are arranged in two rows inparallel with each other. The discharge ports 104 are also arranged intwo rows in parallel with each other in each nozzle. Therefore, whilethe nozzle is scanned on the substrate, the cleaning solution isdischarged via the circular discharge ports 104 of the cleaning solutionat the high pressure, and can substantially linearly be supplied to theregion to be treated of the substrate 103.

Moreover, in the air supply nozzle 102 b, the jet port 105 is formed ina slit shape. Thereby, the air with the high pressure can continuouslyand uniformly be spouted to the region to be treated of the substrate103 in the direction substantially vertical to the scan directionwithout being interrupted. It is to be noted that the jet port is afirst jet region.

As described above, the nozzle for cleaning 102 is constituted tocontinuously and substantially linearly supply each cleaning solutionand high-pressure air to the region to be treated on the substrate 103without being interrupted.

It is to be noted that in the present embodiment, for a structure to beapplied to the substrate 103 having a diameter of about 300 mm, as oneexample, each of the bottom surfaces of the nozzles 102 a to 102 c hastransverse widths W_(1a), W_(1b), W_(1c)=5 mm, and longitudinal lengthL₁=305 mm. Moreover, these three nozzles are integrated and used, andthe whole nozzle for cleaning 102 includes a structure in which thebottom surface has dimensions such as a transverse width W₁=15 mm andlongitudinal length L₁=305 mm.

Here, especially the longitudinal length L₁ of the nozzle for cleaning102 is set to be larger by about several millimeters with respect to thediameter (e.g., 300 mm) of the substrate 103, and each cleaning solutionand air with the high pressure may securely be supplied over the wholesurface of the substrate 103.

It is to be noted that in a cleaning mechanism for use in the presentembodiment, the constitution of the nozzle for cleaning 102 is notlimited to a constitution in which as shown in FIG. 4, a cleaningsolution A 108, high-pressure dry air 109, and cleaning solution B 110are discharged/spouted in order from a front side of the scan direction.For example, the nozzle for cleaning 102 may also be constituted todischarge/spout the cleaning solution A 108 and high-pressure dry air109 in order from the scan direction front side. Moreover, the nozzlefor cleaning 102 may also be constituted so that the high-pressure dryair 109 and cleaning solution B 110 are disposed in order from the scandirection front side. When the dry air with the high pressure and thecleaning solution are simultaneously supplied, the cleaning solution canbe separated from the developing solution, and therefore the cleaning ofthe substrate is possible.

Moreover, in the cleaning treatment mechanism for use in the presentembodiment, it is possible to appropriately change the number andarrangement of the nozzles in the constitution of the nozzle forcleaning 102. Concretely, it is possible to change the numbers ofnozzles for supplying the cleaning solution and nozzles for supplyingthe air and change each constitution and arrangement in accordance withcleaning use. For example, the arrangements of the nozzle for supplyingthe cleaning solution and the nozzle for supplying the air in thenozzles for cleaning 102 can be changed to supply the high-pressure air,ozone water, and high-pressure air, or the high-pressure air, hydrogenwater, and high-pressure air to the region to be treated of thesubstrate 103 in order.

In the present embodiment, the above-described cleaning treatmentmechanism is used to subject the substrate to the cleaning treatment. Inthe present embodiment, in the process of using the above-describedtreating unit to manufacture a semiconductor device as one example,first a developing treatment step, then a cleaning treatment step aresuccessively performed so as to form a pattern on a photosensitive photoresist film on a semiconductor substrate. Therefore, it is assumed asone example that the semiconductor substrate is used in the substrate.

It is to be noted that in the present embodiment the semiconductorsubstrate has a diameter of about 300 mm as one example.

Moreover, as not especially shown, the cleaning treatment mechanism 100includes a nozzle for cleaning the back surface of the substrate 103(=lower surface of the substrate 103) in a predetermined position. Thecleaning solution is appropriately discharged, and dissolution productsor micro particles can be removed from the back surface of the substrate103. At this time, the structure of the nozzle for cleaning the backsurface of the substrate 103 is not especially limited, and a knownstructure may be used. Furthermore, this nozzle may be disposed inpositions such as a backside of the substrate 103 especially to clean aperipheral edge of the back surface of the substrate 103.

A cleaning treatment method of the present embodiment will concretely bedescribed hereinafter with reference to FIGS. 3A, 3B, 4. Here, thetreating unit including the cleaning treatment mechanism 100 shown inFIG. 1 is used.

A film to be processed (e.g., insulating film, or conductive film forwiring), and reflection preventive film are formed beforehand on thesemiconductor substrate. Subsequently, a photosensitive photo resistfilm of a chemical amplification type is successively formed on thefilms. Thereafter, a KrF excimer laser is used in a light source toperform reduced projecting exposure via a reticle for exposure, and thephoto resist film is irradiated with a pattern having a predetermineddimension and shape.

Subsequently, the semiconductor substrate including the photo resistfilm is heat-treated. Thereafter, the above-described movable nozzle fordeveloping is used to perform a so-called scan developing treatment, andthe pattern having the predetermined dimension and shape is formed onthe photo resist film. Here, while the nozzle for developing is scannedat a constant speed of about 60 mm/sec, the predetermined developingsolution is supplied to the photo resist film on the semiconductorsubstrate, a known paddle developing treatment is performed, and thepattern is formed on the photo resist film.

It is to be noted that an alkaline tetramethylammonium aqueous solution(=pH value: 13.4) is used in the developing solution for the photoresist.

Next, the method comprises: performing the developing treatment for apredetermined time; subsequently subjecting the semiconductor substrateto the cleaning treatment; stopping development reaction in the photoresist film; and washing away and removing the developing solution,dissolution product generated by the developing treatment, and microparticles to the outside of the semiconductor substrate.

Here, without rotating the substrate as in the related art, thesemiconductor substrate set to be in a stationary state on the chuck forfixing/supporting 101 is subjected to the cleaning treatment to removethe developing solution, dissolution product generated by the developingtreatment, and micro particles. Thereafter, the drying treatment isperformed to form the pattern of the photo resist having thepredetermined dimension and shape on the semiconductor substrate.

Thereafter, the cleaning treatment method will concretely be described.In the present embodiment, while the nozzle for cleaning 102 is scannedover the whole surface of the semiconductor substrate, the cleaningtreatment is performed to remove the developing solution, dissolutionproduct generated by the developing treatment, and micro particles.

Concretely, as shown in FIGS. 3A, 3B, first the nozzle for cleaning 102is brought close to one end of the semiconductor substrate. Thereafter,while a constant interval is kept from the film of a developing solution107 on a semiconductor substrate 106, the nozzle is moved and scanned inparallel toward the other end, and the cleaning treatment is performed.At this time, while the nozzle for cleaning 102 is scanned, as shown inFIG. 4, the cleaning solution A 108, high-pressure dry air 109, andcleaning solution B 110 are supplied onto the substrate via the cleaningsolution supply nozzle 102 a, air supply nozzle 102 b, and cleaningsolution supply nozzle 102 c. It is to be noted that the photo resistfilm (not shown) is formed on the semiconductor substrate 106.

In the present embodiment, as described above, for the nozzle forcleaning 102, the longitudinal length L₁ (e.g., 305 mm) is larger thanthe diameter (e.g., 300 mm) of the semiconductor substrate 106.Moreover, the width of the direction crossing at right angles to thescan direction of a region in which the cleaning solutions 108, 110 anddry air 109 are supplied is not less than the diameter of thesemiconductor substrate 106. Therefore, the cleaning solutions 108, 110and dry air 109 are supplied to the whole surface of the semiconductorsubstrate 106 in the constitution. Therefore, when the high-pressure dryair 109 is spouted, and the nozzle for cleaning 102 is scanned asdescribed above, the cleaning solution A 108 and cleaning solution B 110are supplied to the whole surface of the semiconductor substrate 106.

In the present embodiment, as one example, the ozone water which is anoxidizing cleaning solution is used in the cleaning solution A 108.Moreover, the hydrogen water which is a reducing cleaning solution isused in the cleaning solution B 110. At this time, ozone concentrationin the ozone water and hydrogen concentration in the hydrogen water areset to about 0.1 to 5 ppm.

Moreover, as shown in FIG. 4, the high-pressure dry air 109 blocks thecleaning solution A 108 and cleaning solution B 110 discharged from thenozzles 102 a and 102 c disposed on opposite sides of the nozzle forcleaning 102 with respect to the film of the developing solution 107 onthe semiconductor substrate 106 to such an extent that the solution filmis slightly left in a thickness of about several hundreds of nanometersto several hundreds of micrometers. The dry air functions as a so-calledair curtain. In this case, the high-pressure dry air 109 is spouted at awind velocity of about 0.1 to 10 m/sec, and requires a pressure and flowrate to such an extent that the cleaning solution A 108 is slightly leftin a solution film shape as the air curtain.

Moreover, at this time, the nozzle for cleaning 102 is brought close toa height of 3 mm or less from the surface of the developing solution 107on the semiconductor substrate 106, and a constant interval is kept tosuch an extent that the nozzle does not contact a photo resist film 112.Thereafter, while the cleaning solution A 108, cleaning solution B 110,and dry air with the high pressure are supplied as described above, thenozzle for cleaning 102 is scanned over the whole surface of thesemiconductor substrate 106 from one end to the other end of thesemiconductor substrate 106. Therefore, the cleaning solution A 108,high-pressure dry air 109, and cleaning solution B 110 are supplied inorder in the region to be treated on the semiconductor substrate 106.

In the present invention, as one example, the nozzle for cleaning 102 isscanned on the same path in the same direction as those of the nozzlefor developing, which supplies the developing solution 107. Moreover, atthis time, the nozzle for cleaning 102 is scanned at a constant speed ofabout 60 mm/sec which is the same speed as a movement speed of thedeveloping nozzle for supplying the developing solution 107.

In this case, since the nozzle is scanned at the substantially constantspeed in the same direction on the same path, as compared with thesupply of the developing solution 107, a time from when the developingsolution 107 is supplied to the whole surface of the semiconductorsubstrate 106 until the solution is replaced with the cleaning solutionA 108 can be controlled to be equal. Therefore, a difference isgenerated in a time to start the development reaction between theregions in a process of forming the pattern in the photo resist film.However, a time for which the developing solution functions in the wholesurface of the semiconductor substrate 106 is set to be equal, and it ispossible to precisely form the pattern in the photo resist film.

It is to be noted that in the present embodiment the replacement of thedeveloping solution with the cleaning solution indicates that componentsof the developing solution are changed by the components of the cleaningsolution, and the function of the developing solution onto the photoresist is stopped.

Moreover, at this time, the cleaning solution (e.g., pure water) isdischarged from a nozzle (not especially shown) for cleaning theabove-described back surface, and the cleaning treatment of the backsurface of the semiconductor substrate 106 is performed. In this manner,when the front surface of the semi-conductor substrate 106 is cleaned,the back surface is cleaned. Thereby, the developing solution,dissolution product, and micro particles removed from the front surfaceof the semiconductor substrate 106 can securely be discharged withoutbeing left in the semiconductor substrate 106 which includes the backsurface. Furthermore, when the front and back surfaces aresimultaneously cleaned/treated, it is possible to securely obtain thecleaning effect of the semi-conductor substrate 106 in a shorter time.

The cleaning treatment is performed as described above, and successivelythe film of the cleaning solution left on the pattern of the photoresist is removed. Here, the semiconductor substrate 106 is rotated at ahigh speed in a range of a rotation speed of 1000 to 20000 rpm to removethe film of the cleaning solution.

It is to be noted that in the present embodiment the nozzle for cleaning102 may be moved with respect to the semiconductor substrate 106 tosupply the respective cleaning solutions and dry air with the highpressure. Therefore, it is also possible to fix the nozzle for cleaning102, discharge the respective cleaning solutions in this state, move thesemiconductor substrate 106 including the chuck for fixing/supporting101, and supply the cleaning solutions 108, 110 and dry air 109 to theregion to be treated on the semiconductor substrate 106.

The cleaning method of the present invention comprises: discharging orjetting the cleaning solution A 108, high-pressure dry air 109, andcleaning solution B 110 in order onto the developing solution 107 on thesemiconductor substrate 106 along the scan direction, and the effect isas follows.

In the nozzle for cleaning 102, the cleaning solution supply nozzle 102a discharges the cleaning solution A 108 to replace the developingsolution 107 mounted on the semiconductor substrate 106 with thecleaning solution A 108. Additionally, the developing solution,dissolution product generated by the developing treatment, and microparticles are washed away to the outside of the semiconductor substrate106.

At this time, the high-pressure dry air 109 is jetted to the dischargedsolution surface of the cleaning solution A 108 with great force.Thereby, as compared with the related-art cleaning method comprising:simply supplying the cleaning solution from above; and rotating andspreading the solution in a plane, the cleaning solution A 108 isequally pressurized in the whole surface of the semiconductor substrate106, and the cleaning effect can be enhanced.

Concretely, when the air supply nozzle 102 b spouts the high-pressuredry air 109, the developing solution 107 replaced with the cleaningsolution A 108 is pressurized in a direction of the peripheral edge, andsecurely discharged to the outside of the semiconductor substrate 106.Moreover, the high-pressure dry air 109 prevents these dischargedsolutions from sticking to the region subjected to the cleaningtreatment on the semiconductor substrate 106. Additionally, at thistime, the high-pressure dry air 109 needs to be linearly connected in adirection substantially vertical to the scan direction without beinginterrupted on the semiconductor substrate 106 to form the so-called aircurtain.

Furthermore, after the high-pressure dry air 109 is spouted, thecleaning solution B 110 is continuously discharged, and a small amountof developing solution 107 remaining in the pattern of the photo resistis washed away to the outside of the semiconductor substrate 106. Atthis time, the cleaning solution B 110 is continuously discharged to theregion to which the high-pressure dry air 109 is spouted. It is possibleto simultaneously wash away and remove the dissolution product, microparticles, and deposit to the outside of the semiconductor substrate 106so as to be prevented from sticking to the pattern of the photo resist.

As described above, in the present embodiment, the ozone water having anoxidizing property is used in the cleaning solution A 108. The ozonewater oxidizes the dissolution product generated in the process of thedeveloping treatment, micro particles, and deposit. Especially, there isan effect of oxidizing an organic matter, decomposing a molecularstructure, and dividing the matter into particles. Therefore, after thedeveloping treatment, the organic matter is inhibited from sticking tothe photo resist again, and the generation of defect portions of theresist pattern can largely be reduced.

At this time, the ozone water may also be used in a low concentration ofabout 1 ppm. With this degree of concentration, the ozone water does notdamage the pattern of the photo resist. In this case, the waterfunctions to such an extent that only a side wall portion of the patternof the photo resist is slightly etched. Therefore, roughness of thepattern dimension of the photo resist (=local dispersion) is reduced,and an effect is obtained that the uniformity of the dimension isenhanced in the plane.

Moreover, as described above, the hydrogen water having the reducingproperty is used in the cleaning solution B 110 in the presentembodiment.

After the organic matter is decomposed by the ozone water as describedabove, the particles of the organic matter left without being washedaway sometimes stick to the surface of the photo resist film. When theparticles of the organic matter adhere to the pattern of the photoresist, the defect portions (=dispersion of the pattern dimension) aregenerated in the resist pattern, and errors of the dimension and shapeare generated in the subsequent etching step.

To solve the problem, as in the present embodiment, after the ozonewater is supplied, the hydrogen water is discharged, and the surfaces ofthe particles of the organic matter are thereby reduced, and detachedfrom the surface of the photo resist film again. Thereby, additionally,contaminants and impurities are washed away to the outside of thesemiconductor substrate 106, and the cleaning treatment can furthersecurely be performed.

In the present embodiment, the ozone water is used in the cleaningsolution A 108, and the hydrogen water is used in the cleaning solutionB 110. These solutions are successively and continuously supplied to thedeveloping solution 107 on the semiconductor substrate 106. In thiscase, the ozone water is an oxidizing aqueous solution, whereas thehydrogen water is a reducing aqueous solution. When the ozone andhydrogen waters are alternately mixed, properties of the solutions aremutually offset, and the function of the cleaning solution, and thecleaning effect are deteriorated. Therefore, when the cleaning solutionshaving opposite properties are continuously used in the process of thecleaning treatment, a mutually mixed amount is reduced, and it isnecessary to prevent the deterioration of the function of the cleaningsolution and the deterioration of the cleaning effect.

To solve the problem, in the present embodiment, the high-pressure dryair 109 is spouted to form the air curtain between the cleaning solutionA 108 (e.g., ozone water) and cleaning solution B 110 (e.g., hydrogenwater), the mutually mixed amount is thereby reduced, and it is possibleto prevent the deterioration of the function of the cleaning solutionand the deterioration of the cleaning effect.

When the cleaning solutions having the opposite properties are used inthis manner, the dry air with the high pressure is spouted to separatethe cleaning solutions from each other, the so-called air curtain isformed to inhibit the cleaning solutions from being mixed with eachother, and this is effective in keeping the cleaning effect to beconstantly high.

It is to be noted that in the present embodiment the ozone water is usedin the cleaning solution A and the hydrogen water is used in thecleaning solution B. However, as long as effects similar to these can beobtained, it is possible to change the cleaning solution to anothertype. For example, the ozone water is used in the cleaning solution A,pure water is used in the cleaning solution B, and the cleaningtreatment can be performed as described above. Moreover, surfactant isadded to the pure water for use in the cleaning solution B, and theimpurities and contaminants can more effectively be removed.

Moreover, in the present embodiment, the high-pressure dry air 109 isjetted to pressurize the films of the cleaning solution A 108 andcleaning solution B 110, and the thickness can be reduced to aboutseveral hundreds of nanometers to several hundreds of micrometers rightunder the air curtain. That is, amounts of the cleaning solution A 108and cleaning solution B 110 are reduced to slight amounts in a region inwhich the high-pressure dry air 109 has passed in the semiconductorsubstrate 106. Therefore, thereafter, without throwing off the cleaningsolution by high-speed rotation (=rotation speed: 1000 to 4000 rpm) asin the related-art method, the effect of the drying treatment can easilybe given to the semiconductor substrate 106. In this case, since aphysical load (=centrifugal force, water flow of the cleaning solution,and the like) is not applied to the semiconductor substrate 106, evenwith the use of the semiconductor substrate having a large bore diameter(e.g., diameter of about 300 mm), it is possible to easily impart theeffect of the drying treatment without damaging the pattern of the photoresist.

The effect of the present embodiment will be compared with that of theuse of the related-art cleaning method, and described hereinafter withreference to FIGS. 5A, 5B.

Here, the method comprises: first scanning the nozzle for cleaning foruse in the present embodiment as described above; supplying the ozonewater, air, and hydrogen water in order as one example; carrying out thecleaning treatment of the substrate; and thereafter measuringdimensional uniformity and the number of defect portions of the photoresist pattern. Moreover, here, the method comprises: repeating thecleaning treatment about three times in one example; and measuring thedimensional uniformity in the substrate plane and the number of defectportions of the pattern in each treatment. FIGS. 5A, 5B show the effectsof three cleaning treatments using the present-embodiment method, andrelated-art cleaning method. The effect of the present embodiment isconsidered by comparing an average value of three cleaning treatmentswith the value of the related-art cleaning method. As a result, it hasbeen found that the effects shown in FIGS. 5A, 5B are obtained in thepresent embodiment.

FIG. 5A shows results of measurement of the dimensional uniformity ofthe photo resist pattern in the plane of the substrate (=wafer) in eachof the present-embodiment method and related-art cleaning method. In themethod according to the present embodiment, as shown in FIG. 5A, thedimensional uniformity can be enhanced by about 20% as compared with therelated-art cleaning method. Here, the dimensional uniformity indicatesa degree of dispersion of dimension obtained as a result of measurementperformed in a plurality of points of patterns using the patterns whichhave to have the same dimension in design as objects.

Moreover, FIG. 5B shows results of the measurement of the number ofdefect portions generated in the photo resist pattern in each of thepresent-embodiment and related-art methods. In the present embodiment,as shown in FIG. 5B, as a result of the measurement of the number ofdefect portions of the photo resist pattern on the substrate (=wafer),the number can be decreased by 65% as compared with the use of therelated-art cleaning method. Here, the defect portion indicates a statein which the impurities and contaminants of the organic matters stick tothe photo resist pattern and an error is generated in the dimension.

In this manner, the present embodiment relates to the semiconductorsubstrate which has a large bore diameter (e.g., diameter of about 300mm). Additionally, it is possible to enhance the cleaning effect in thedeveloping treatment of the photo resist as compared with therelated-art cleaning method.

It is to be noted that a nozzle 120 integrally constituted of the nozzlefor cleaning 102 and nozzle for developing 121 as shown in FIG. 30 mayalso be used. As shown in FIG. 30, the nozzle 120 includes the nozzlefor cleaning 102 and nozzle for developing 121. A discharge port 122 fordischarging the developing solution is formed in a slit shape in thenozzle for developing 121. A length of a direction of the discharge port122 crossing at right angles to the scan direction is equal to or morethan the maximum diameter or longest side of the substrate. Thereby, thedeveloping solution can uniformly be supplied to the region to betreated of the substrate 103 continuously without being interrupted in adirection substantially vertical to the scan direction. It is to benoted that the nozzle for developing 121 forms a third discharge region.It is to be noted that the position of the nozzle for developing 121 isnot limited to a front side of the nozzle for cleaning 102 with respectto the scan direction as shown in FIG. 30. For example, the nozzle fordeveloping 121 may also be disposed on a rear side of the nozzle forcleaning 102 with respect to the scan direction.

With this nozzle, the developing treatment is not performed in parallelwith the cleaning treatment. At a developing treatment time, the nozzlefor developing 121 discharges the developing solution, and the nozzlefor cleaning 102 does not discharge the cleaning solution or jet out thegas. Moreover, at a cleaning treatment time, the nozzle for cleaning 102discharges the cleaning solution and jets out the gas, and the nozzlefor developing 121 does not discharge the developing solution.

It is to be noted that in the above-described embodiment the developingsolution has been described as a treating solution. However, an etchingsolution may also be used as the treating solution.

Second Embodiment

In the present embodiment, the developing, cleaning, and dryingtreatments are performed in order to form the pattern which has apredetermined dimension and shape in the region to be treated of thesubstrate in the same manner as in the first embodiment. Moreover, inthe present embodiment, a so-called developing treatment apparatus of asingle wafer process system is used in which one substrate cancontinuously be subjected to the process of the developing, cleaning,and drying treatments in one apparatus.

A treatment unit which can continuously perform the developing,cleaning, and drying treatments with respect to the substrate isdisposed in the developing treatment apparatus. In the presentembodiment, each corresponding treating mechanism is used to perform aseries of processes of the developing, cleaning, and drying treatmentsin this treating unit.

As one example, the developing treatment mechanism is disposed toperform the known scan developing treatment in this treating unit. In apart of this developing treatment mechanism, the movable nozzle fordeveloping is disposed which can move in the vertical and horizontaldirections so as to discharge the developing solution and scan on thesubstrate. In this nozzle for developing, the elongated rectangularslit-shaped constitution is disposed to supply the developing solutionto the region to be treated on the substrate by the uniform amount.

Moreover, in addition to the above-described constitution, as shown inFIG. 6, the treating unit also includes the cleaning treatmentmechanism. The constitution and operation of the cleaning treatmentmechanism disposed in the treating unit which performs the developing,cleaning, and drying treatments will be described hereinafter in detailwith reference to FIG. 6.

It is to be noted that FIG. 6 shows the main constituting part relatedto a cleaning treatment mechanism 200.

The unit for performing the developing and cleaning treatments includesthe cleaning treatment mechanism 200 shown in FIG. 6. The cleaningtreatment mechanism 200 includes main the constituting components of achuck for fixing/supporting 201, and cleaning nozzle 202. Moreover,these chuck for fixing/supporting 201 and cleaning nozzle 202 areconstituted in movable types, and can independently be moved.

In the cleaning treatment mechanism 200, after the developing treatmentis performed, a substrate 203 is laid and fixed onto the chuck forfixing/supporting 201, the predetermined cleaning solution is suppliedfrom the cleaning nozzle 202, and the surface of the substrate 203 issubjected to the cleaning treatment.

It is to be noted that the substrate 203 has a diameter of about 300 mmin one example.

In the present embodiment, the cleaning nozzle 202 is constituted offive nozzles 202 a to 202 e. A moving mechanism 215 moves the nozzle 202in parallel with the surface of the substrate 203.

Moreover, as not especially shown, the cleaning treatment mechanism 200includes a nozzle for cleaning the back surface (lower surface) of thesubstrate 203 in the predetermined position. The cleaning solution isappropriately discharged, and the dissolution products or microparticles can be removed from the back surface of the substrate 203. Atthis time, the structure of the nozzle for cleaning the back surface ofthe substrate 203 is not especially limited, and the known structure maybe used. Furthermore, this nozzle may be disposed in the positions suchas the backside of the substrate 203 especially to clean the peripheraledge of the back surface of the substrate 203.

In the present embodiment, as described above, the cleaning nozzle 202of the movable type is used. Concretely, it is possible to move thecleaning nozzle 202 in parallel with the surface of the substrate 203while keeping a constant interval. Moreover, as one example, thecleaning nozzle 202 is constituted of five nozzles 202 a to 202 e.

In the present embodiment, as shown in FIG. 7, the cleaning nozzle 202is constituted by disposing five nozzles 202 a to 202 e adjacent to oneanother and combining the nozzles.

In the present embodiment, three nozzles 202 a, 202 c, 202 e spout theair with the high pressure onto the region to be treated of thesubstrate 203 as first to third jet regions. Moreover, the nozzles 202 band 202 d discharge the cleaning solution to the region to be treated onthe substrate 203 as the nozzles for supplying the cleaning solution.

It is to be noted that the nozzles 202 a to 202 e can be operated toindependently discharge or jet out the cleaning solutions A, B, and airwith the high pressure.

Here, in the cleaning nozzle 202, the first air supply nozzle 202 a,first cleaning solution supply nozzle 202 b, second air supply nozzle202 c, second cleaning solution supply nozzle 202 d, and third airsupply nozzle 202 e are disposed in order and adjacent to one anotheralong the scan direction.

Moreover, as shown in FIG. 7, the respective nozzles 202 a to 202 e areformed in elongated rectangular slit shapes, and a large number ofdischarge ports of the cleaning solution 204 for discharging thecleaning solution, and a blow-off port for air 205 are formed in thebottom surface disposed opposite to the substrate 203.

Here, the respective cleaning solution supply nozzles 202 b, 202 d arearranged in parallel in two rows. Moreover, a large number of circularcleaning solution discharge ports 204 are alternately arranged in thebottom surfaces of the respective cleaning solution supply nozzles 202b, 202 d in a so-called porous structure. Here, the discharge ports 204of the cleaning solution are formed in circular shapes, and eachcleaning solution can be discharged to the outside with the highpressure. Moreover, the discharge ports 204 of the cleaning solution arealternately arranged in two rows to form the row extending in parallelwith each other in the respective cleaning solution supply nozzles 202b, 202 d.

In the process of performing the cleaning treatment, the discharge ports204 of the cleaning solution simultaneously discharge the predeterminedcleaning solution, and each of the cleaning solution supply nozzles 202b, 202 d can uniformly supply the predetermined cleaning solution to theregion to be treated on the substrate 203 in the direction vertical tothe scan direction. At this time, as described above, the respectivecleaning solution supply nozzles 202 b, 202 d are arranged in two rowsin parallel, and the discharge ports 204 of the cleaning solution arealso arranged in two rows in parallel with one another in each nozzle.Therefore, during the scanning, the circular cleaning solution dischargeports 204 discharge the cleaning solution with the high pressure, andcan substantially linearly supply the solution to the region to betreated of the substrate 203. A region of the nozzle 202 b in which thedischarge ports 204 are arranged is a first discharge region. A regionof the nozzle 202 d in which a plurality of discharge ports 104 arearranged is a second discharge region.

Moreover, the blow-off port for air 205 is formed in the elongatedrectangular slit shape in each of the first to third air supply nozzles202 a, 202 c, 202 e. Thereby, the air with the high pressure canuniformly be spouted to the region to be treated of the substrate 203continuously without being interrupted in the direction vertical to thescan direction. A region of the first air supply nozzle 202 a in whichthe blow-off port 205 is formed is a third jet region. A region of thesecond air supply nozzle 202 c in which the blow-off port 205 is formedis a first jet region. A region of the third air supply nozzle 202 e inwhich the blow-off port 205 is formed is a second jet region.

As described above, the cleaning nozzle 202 is constituted so that eachcleaning solution and air with the high pressure are substantiallylinearly supplied to the region to be treated of the substrate 203continuously without being interrupted.

It is to be noted that in the present embodiment each of the bottomsurfaces of the nozzles 202 a to 202 e has a transverse width (W_(2a),W_(2b), W_(2c), W_(2d), W_(2e))=5 mm, and longitudinal length L₂=205 mm.Moreover, these five nozzles are integrated and used, and the wholecleaning nozzle 202 includes the structure in which the bottom surfacehas the dimensions such as a transverse width W₂=25 mm and longitudinallength L₂=305 mm.

Here, especially the longitudinal length L₂ of the cleaning nozzle 202is set to be larger than the diameter (e.g., 300 mm) of the substrate203 by about several millimeters, and the cleaning solution and air withthe high pressure may securely be supplied over the whole surface of thesubstrate 203.

Moreover, in the cleaning treatment mechanism for use in the presentembodiment, for the constitution of the cleaning nozzle 202, the numberand arrangement of nozzles can appropriately be changed. Concretely, thenumber of the nozzles for supplying the cleaning solution and forsupplying the air is changed in accordance with a cleaning purpose, andeach constitution and arrangement of the nozzles can be changed.

In the present embodiment, the above-described cleaning treatmentmechanism is used to subject the substrate to a cleaning treatment step.In the present embodiment, a substrate treating method will be describedin terms of one example of the process of manufacturing thesemiconductor device in the same manner as in the first embodiment. Inthis case, the developing treatment step and then the cleaning treatmentstep are successively performed so as to form the pattern in thephotosensitive photo resist film on the semiconductor substrate.Therefore, the semiconductor substrate is used as one example in thesubstrate.

It is to be noted that in the present embodiment a semiconductorsubstrate having a diameter of about 300 mm is used as one example.

The cleaning treatment method of the present embodiment will concretelybe described hereinafter with reference to FIG. 8. Here, it is assumedthat the treating unit including the cleaning treatment mechanism 200shown in FIG. 8 is used.

The reflection preventive film is formed beforehand on the semiconductorsubstrate. Subsequently, the photosensitive photo resist film of thechemical amplification type is successively formed on the film in aknown method. Thereafter, the KrF excimer laser is used in the lightsource to perform the reduced projecting exposure via the reticle forexposure, and the photo resist film is irradiated with the patternhaving the predetermined dimension and shape.

Subsequently, the semiconductor substrate including the photo resistfilm is heat-treated. Thereafter, the above-described movable nozzle fordeveloping is used to perform the so-called scan developing treatment,and the pattern having the predetermined dimension and shape is formedon the photo resist film. Here, while the nozzle for developing isscanned at the constant speed of about 60 mm/sec, the predetermineddeveloping solution is supplied to the photo resist film on thesemiconductor substrate, the known paddle developing treatment isperformed, and the pattern is formed on the photo resist film.

It is to be noted that an alkaline tetramethylammonium aqueous solution(=pH value: 13.4) is used in the developing solution for the photoresist.

Next, the method comprises: performing the developing treatment for thepredetermined time; subsequently subjecting the semiconductor substrateto the cleaning treatment; stopping the development reaction in thephoto resist film; and washing away and removing the developingsolution, dissolution product generated by the developing treatment, andmicro particles to the outside of the semiconductor substrate.

Here, without rotating the substrate as in the related art, thesemiconductor substrate set to be in the stationary state on the chuckfor fixing/supporting 201 is subjected to the cleaning treatment toremove the developing solution, dissolution product generated by thedeveloping treatment, and micro particles. Thereafter, the dryingtreatment is performed to form the pattern of the photo resist havingthe predetermined dimension and shape on the semiconductor substrate.

Thereafter, the cleaning treatment method will concretely be described.In the present embodiment, while the nozzle for cleaning 102 is scannedover the whole surface of the semiconductor substrate, the cleaningtreatment is performed to remove the developing solution, dissolutionproduct generated by the developing treatment, and micro particles. Itis to be noted that the surface of the semiconductor substrate is asurface in which a semiconductor device is formed.

Concretely, in the same manner as in the first embodiment, first thecleaning nozzle 202 is brought close to one end of a semiconductorsubstrate 206. Thereafter, while the constant interval is kept from thefilm of a developing solution 207 on the semiconductor substrate 206,the nozzle is moved and scanned in parallel toward the other end, andthe cleaning treatment is performed. At this time, while the cleaningnozzle 202 is scanned, as shown in FIG. 8, three air supply nozzles 202a, 202 c, 202 e, and two cleaning solution supply nozzles 202 b, 202 dsupply high-pressure dry airs 208, 210, 212, cleaning solution A 209,and cleaning solution B 211 to the developing solution 207 as oneexample. It is to be noted that reference numeral 216 denotes the photoresist film.

In the present embodiment, as described above, for the cleaning nozzle202, the longitudinal length L₂ (e.g., 305 mm) is not less than thediameter (e.g., 300 mm) of the semiconductor substrate 206. Moreover,the width of the direction crossing at right angles to the scandirection of the region in which the dry airs 208, 210, 212 and cleaningsolutions 209, 211 are supplied is not less than the diameter of thesemiconductor substrate 206. Therefore, the dry airs 208, 210, 212 andcleaning solutions 209, 211 are supplied to the whole surface of thesemiconductor substrate 206 in the constitution. Therefore, while thehigh-pressure dry airs 208, 210, 212 are spouted, and the cleaningnozzle 202 is scanned as described above, the cleaning solution A 209and cleaning solution B 211 are supplied to the whole surface of thesemiconductor substrate 203.

In the present embodiment, the respective air supply nozzles 202 a, 202c, 202 e spout the high-pressure dry airs 208, 210, 212 as one example.Moreover, in the present embodiment, as one example, the ozone waterwhich is an oxidizing cleaning solution is used in the cleaning solutionA 209. Moreover, the hydrogen water which is a reducing cleaningsolution is used in the cleaning solution B 211. At this time, theconcentrations of the ozone water and hydrogen water are set to about0.1 to 5 ppm.

Moreover, as shown in FIG. 8, each of the high-pressure dry airs 208,210, 212 functions as the so-called air curtain. The high-pressure dryairs 208, 212 are spouted to the film of the developing solution 207 onthe semiconductor substrate 206 to flow over the cleaning solution A 209discharged from the nozzle 202 b and the cleaning solution B 211discharged from the nozzle 202 d from opposite sides of the cleaningnozzle 202 in the scan direction, and function so as to block thesesolutions from the outside. Moreover, the high-pressure dry air 210slightly blocks between the cleaning solution A 209 and cleaningsolution B 211 with respect to the film of the developing solution 207on the semiconductor substrate 206 in a thickness of about severalhundreds of nanometers to several hundreds of micrometers to such anextent that the solution film is left.

In this case, the high-pressure dry airs 208, 210, 212 are spouted at awind velocity of about 0.1 to 10 m/sec, and each air requires thepressure and flow rate to such an extent that the air functions as theair curtain.

Moreover, at this time, the cleaning nozzle 202 is brought close to aheight of 3 mm or less from the surface of the developing solution 207on the semi-conductor substrate 206, and the constant interval is keptto such an extent that the nozzle does not contact the pattern on thephoto resist. Thereafter, while the cleaning solution A 209, cleaningsolution B 211, and high-pressure dry airs 208, 210, 212 are suppliedfrom the cleaning nozzle 202 as described above, the nozzle is scannedover the whole surface of the semiconductor substrate 206 from one endto the other end of the semiconductor substrate 206. Therefore, thehigh-pressure dry air 208, cleaning solution A 209 (e.g., ozone water),high-pressure dry air 210, cleaning solution B 211, and high-pressuredry air 212 are supplied in order in the region to be treated on thesemiconductor substrate 206.

In the present invention, as one example, the cleaning nozzle 202 isscanned on the same path in the same direction as those of the nozzlefor developing, which supplies the developing solution 207. Moreover, atthis time, the cleaning nozzle 202 is scanned at the constant speed ofabout 60 mm/sec which is the same as the movement speed of the nozzlefor supplying the developing solution 207.

In this case, since the nozzle is scanned at the substantially sameconstant speed in the same direction on the same path, as compared withthe supply of the developing solution 207, the time from when thedeveloping solution 207 is supplied to the whole surface of thesemiconductor substrate 206 until the solution is replaced with thecleaning solution A 209 can be controlled to be equal. Therefore, thedifference is generated in the time to start the development reactionbetween the regions in the process of forming the pattern in the photoresist film. However, the time for which the developing solutionfunctions in the whole surface of the semiconductor substrate 206 is setto be equal, and it is possible to form the pattern in the photo resistfilm with good precision.

It is to be noted that in the present embodiment the replacement of thedeveloping solution with the cleaning solution indicates that thecomponents of the developing solution are changed by the components ofthe cleaning solution, and the function of the developing solution ontothe photo resist is stopped.

Moreover, at this time, the cleaning solution (e.g., pure water) isdischarged from the nozzle (not especially shown) for cleaning theabove-described back surface, and the cleaning treatment of the backsurface of the semiconductor substrate 206 is performed. In this manner,when the front surface of the semiconductor substrate is cleaned, theback surface is cleaned. Thereby, the developing solution, dissolutionproduct, and micro particles removed from the front surface of thesemiconductor substrate 206 can securely be discharged without beingleft in the semiconductor substrate. Furthermore, when the front andback surfaces are simultaneously cleaned/treated, it is possible tosecurely perform the cleaning treatment of the semiconductor substrate206 in short time.

The cleaning treatment is performed as described above, successively theairs are supplied to the surface of the semiconductor substrate 206, andthe cleaning solution slightly left on the pattern of the photo resistfilm is removed. In this manner, in the present embodiment, the cleaningsolution is vaporized without rotating the semiconductor substrate 206,and the drying treatment can be performed. Therefore, even when thesemiconductor substrate having a large bore diameter (e.g., 300 mm) isused, the drying treatment can be performed without damaging the patternof the photo resist, or causing the pattern fall.

It is to be noted that in the present embodiment the cleaning nozzle 202is relatively moved with respect to the substrate, that is, thesemiconductor substrate 106, and the respective cleaning solutions andhigh-pressure dry air may be supplied. Therefore, it is also possible tofix the cleaning nozzle 202, discharge the respective cleaning solutionsin this state, move the semiconductor substrate 206 including the chuckfor fixing/supporting 201, and supply the respective cleaning solutions209, 211, and high-pressure dry airs 208, 210, 212 to the region to betreated on the semiconductor substrate 106 as described above.

The cleaning method of the present embodiment comprises: discharging orspouting the high-pressure dry air 208, cleaning solution A 209,high-pressure dry air 210, cleaning solution B 211, and high-pressuredry air 212 to the developing solution 207 on the substrate, that is,the semiconductor substrate 206 in order along the scan direction. Theeffect is as follows.

When the first air supply nozzle 202 a spouts the high-pressure dry air208 in the cleaning nozzle 202, the developing solution 207 on thesemiconductor substrate 206 is pressurized, and the film thickness isreduced to about several hundreds of micrometers.

At this time, the high-pressure dry air 208 forms the air curtain, andprevents the developing solution 207 from sticking to the regionsubjected to the cleaning treatment again. Additionally, the cleaningsolution A 209 supplied soon after the developing solution iseffectively prevented from going ahead, that is, sticking to the regionwhich has not been cleaned.

Moreover, the first cleaning solution supply nozzle 202 b of thecleaning nozzle 202 discharges the cleaning solution A 209. Thedeveloping solution 207 on the semiconductor substrate 206 is replacedwith the component of the cleaning solution A 209. Furthermore, thecleaning solution A 209 washes away the dissolution product and microparticle in the solution to the outside of the semiconductor substrate206.

At this time, the first air supply nozzle 202 a spouts the high-pressuredry air 208, the film thickness of the developing solution 207 on thesemiconductor substrate 206 is reduced as described above, and theamount of the developing solution 207 decreases and is pressurized.Therefore, the cleaning effect is enhanced.

Furthermore, the second air supply nozzle 202 c spouts the high-pressuredry air 210. The region below the first cleaning solution supply nozzle202 b is partitioned by the air curtain on opposite sides, and blockedin the scan direction. Therefore, a region in which the cleaningsolution A 209 functions is limited to the region partitioned by thehigh-pressure dry airs 208, 210. The film thickness of the developingsolution 207 in the region is reduced as described above. Additionally,the amount of the solution is sufficiently reduced as compared with thecleaning solution A 209. In this case, the amount of the cleaningsolution A 209 consumed by the developing solution 207 decreases in theprocess of performing the cleaning treatment, and it is possible to keepthe concentration to be substantially constant from a supply time.Therefore, the cleaning nozzle 202 is scanned, thereby the developingsolution 207 is momentarily replaced with the cleaning solution A 209(e.g., ozone water), and it is possible to perform the cleaningtreatment in the whole surface of the semiconductor substrate 206 inshort time.

Moreover, the developing solution 207 and cleaning solution replacedwith the cleaning solution A 209 are discharged to the outside of thesemiconductor substrate 206 from a gap along the air curtain. After thecleaning nozzle 202 is scanned, the developing solution 207 can beprevented from returning onto the substrate.

Additionally, at this time, the high-pressure dry airs 208, 210 need tobe linearly connected to form the air curtain without being interruptedin a direction substantially vertical to a direction in which thesemiconductor substrate 206 is scanned.

In the cleaning solution supply nozzle 202, subsequent to thehigh-pressure dry air 210, the cleaning solution B 211, andhigh-pressure dry air 212 are successively discharged or spouted.

In the present embodiment, the ozone water is used in the cleaningsolution A 209. This ozone water oxidizes the dissolution productgenerated in the process of performing the developing treatment, microparticles, and deposits. Especially there is an effect that the organicmatter is oxidized and the molecular structure is decomposed and finelydivided into particles. Therefore, after the developing treatment, theorganic matter is inhibited from sticking to the photo resist against,and the generation of the defect portions of the resist pattern canlargely be reduced.

Moreover, at this time, the ozone water may be used in low concentrationof about 1 ppm. With this degree of concentration, the ozone water doesnot damage the pattern of the photo resist. In this case, since only theside wall portion of the pattern of the photo resist is slightly etched,the roughness (=local dispersion) of the dimension of the resist patternis reduced. An effect is obtained that the dimensional uniformity isenhanced in the plane.

Furthermore, as described above, in the present embodiment, the hydrogenwater which is the cleaning solution having the reducing property isused in the cleaning solution B 211.

After the organic matter is decomposed by the ozone water as describedabove, the particles of the organic matter left without being washedaway stick to the surface of the photo resist film. When the particlesof the organic matter stick to the pattern of the photo resist, thedefect portion (=dispersion of the pattern dimension) is generated inthe resist pattern, and the errors of the dimension and shape aregenerated in the subsequent etching step.

To solve the problem, as in the present embodiment, after the ozonewater is supplied, the hydrogen water is discharged. Thereby, thesurfaces of the particles of the organic matter are reduced, and areseparated from the surface of the photo resist film again. Thereby,additionally, the contaminants and impurities are washed away to theoutside of the semiconductor substrate 206, and the cleaning treatmentcan further securely be performed.

In the present embodiment, the ozone water is used in the cleaningsolution A 209, the hydrogen water is used in the cleaning solution B211, and these are continuously supplied to the developing solution 207on the semiconductor substrate 206. In this case, the ozone water is theoxidizing aqueous solution, whereas the hydrogen water is the reducingaqueous solution. When the ozone and hydrogen waters are mutually mixedin the process of performing the cleaning treatment, the properties ofthe solutions are mutually offset, and the function of the cleaningsolution, and the cleaning effect are deteriorated.

Therefore, when the cleaning solutions having the opposite propertiesare used, in the same manner as in the first embodiment, the dry airwith the high pressure is spouted so as to separate both the cleaningsolutions, and the so-called air curtain is formed between the solutionsto inhibit the cleaning solutions from being mixed. This is effective inkeeping the cleaning effect to be constant and high.

It is to be noted that in the present embodiment the ozone water is usedin the cleaning solution A, and the hydrogen water is used in thecleaning solution B. However, as long as the effects similar to thesecan be obtained, it is possible to change the cleaning solution toanother type. For example, the ozone water is used in the cleaningsolution A, the pure water is used in the cleaning solution B, and thecleaning treatment can be performed as described above. Moreover, thesurfactant is added to the pure water for use in the cleaning solutionB, and the impurities and contaminants can more effectively be removed.

In the present embodiment, as described above, while the cleaningsolution A 209 and cleaning solution B 211 are discharged, thehigh-pressure dry airs 208, 212 are spouted on opposite sidesbefore/after the solutions, and the cleaning treatment is performed inthis manner. At this time, the high-pressure dry airs 208, 212 functionas the air curtain, and block the cleaning solution A 209 and cleaningsolution B 211 from the front/back side in the scan direction of thecleaning nozzle 202. Therefore, the cleaning solution A 209 and cleaningsolution B 211 are not diffused to the outside, and are supplied to thedeveloping solution 207 in a concentrated manner, so that the pressureincreases and the cleaning effect can further be enhanced the more.

The effect of the present embodiment will be compared with that of theuse of the related-art cleaning method, and described hereinafter withreference to FIGS. 9A, 9B.

Here, the method comprises: first scanning the nozzle for cleaning foruse in the present embodiment as described above; supplying the air,ozone water, air, hydrogen water, and air in order as one example;carrying out the cleaning treatment of the substrate; and thereaftermeasuring dimensional uniformity and the number of defect portions ofthe photo resist pattern. Moreover, here, in the same manner as in thefirst embodiment, the method comprises: repeating the cleaning treatmentabout three times in one example; and measuring the dimensionaluniformity in the substrate plane and the number of defect portions ofthe pattern in each treatment. FIGS. 9A, 9B show the results of threecleaning treatments using the present-embodiment method, and related-artcleaning method. The effect of the present embodiment is considered bycomparing the average value of three cleaning treatments with the valueof the related-art cleaning method. As a result, it has been found thatthe effects shown in FIGS. 9A, 9B are obtained in the presentembodiment.

FIG. 9A shows the results of measurement of the dimensional uniformityof the photo resist pattern in the plane of the substrate (=wafer) ineach of the present-embodiment method and related-art cleaning method.In the method according to the present embodiment, as shown in FIG. 9A,in the same manner as in the first embodiment, the dimensionaluniformity can be enhanced by about 20% as compared with the related-artcleaning method. Here, the dimensional uniformity indicates the degreeof dispersion of dimension obtained as a result of measurement performedin a plurality of points of the patterns using the patterns which haveto have the same dimension in the design as the objects.

Moreover, FIG. 9B shows the results of the measurement of the number ofdefect portions generated in the photo resist pattern in each of thepresent-embodiment method and related-art cleaning method. In thepresent embodiment, as shown in FIG. 9B, in the same manner as in thefirst embodiment, as a result of the measurement of the number of defectportions of the photo resist pattern on the substrate, the number can bedecreased by 65% as compared with the use of the related-art cleaningmethod. Here, the defect portion indicates the state in which theimpurities and contaminants of the organic matters stick to the photoresist pattern and the error is generated in the dimension.

In this manner, the present embodiment relates to the semiconductorsubstrate which has a large bore diameter (e.g., diameter of about 300mm). Additionally, it is possible to enhance the cleaning effect in thedeveloping treatment of the photo resist as compared with therelated-art cleaning method.

In the present embodiment, it is also possible to generate bubblesinside the cleaning solution, allow the bubbles to physically function,and further enhance the cleaning effect. In this case, as shown in FIG.10, a part (=small air) 213 of the high-pressure dry air 210 spoutedfrom the second air supply nozzle 202 c is mixed in the cleaningsolution A 209 discharged from the nozzle 202 b before reaching thedeveloping solution 207 on the semiconductor substrate 206 in the regionpartitioned by the air curtains 208, 210 on the opposite sides, andbubbles 214 can be generated in the cleaning solution A 209. The bubbles214 generate a pressure difference inside the cleaning solution A 209,give impact to the dissolution product and micro particles sticking tothe surface of the pattern of the photo resist, easily remove these, andcan further enhance the cleaning effect.

In this case, in the cleaning nozzle 202, at least a nozzle can be usedwhich is processed so as to spout a part of one of the high-pressure dryairs 208, 210 toward the adjacent cleaning solution A 209.

Concretely, the nozzle is processed such that the air blow-off ports 205of the nozzles 202 a, 202 c spout the high-pressure air to form the aircurtain on the opposite sides of the first cleaning solution supplynozzle 202 b and at least a part of the high-pressure dry air 208 or 210is spouted toward the adjacent cleaning solution A 209. Here, in atleast one of the nozzles 202 a, 202 c, a blow-off port (e.g., holeshape) is disposed in the vicinity of the nozzle 202 b at apredetermined interval from the air blow-off port 205, and a part of thehigh-pressure dry air 208 or 210 is spouted in the constitution.

It is to be noted that as one example, the bubbles are generated in thecleaning solution A 209 to perform the cleaning treatment. However, thecleaning nozzle 202 is similarly processed, and the bubbles can begenerated in the cleaning solution B 211 in order to perform thecleaning treatment. Moreover, as in the present embodiment, each of thehigh-pressure dry airs 208, 210, 212 functions, and the amount of thedeveloping solution 207 is reduced to a slight amount on thesemiconductor substrate 206. In this case, the cleaning solution A 209,that is, the ozone water reaches the photo resist film during thedevelopment reaction without dropping in the concentration in thesolution, and a surface layer portion is brought in an oxidized state bythe ozone water.

When even the surface layer portion of the photo resist film is oxidizedin this manner, the particles of the organic matter can further securelybe prevented from sticking again. Therefore, in the present embodiment,the dissolution product, micro particle, deposit, and especially organicmatter are effectively removed. In the process of performing thecleaning treatment, it is possible to remarkably reduce the generationof the defect portion of the developed pattern.

Moreover, in the present embodiment, the high-pressure dry airs 208,210, 212 are spouted, thereby the films of the cleaning solution A 209and cleaning solution B 211 are pressurized, and the thickness can bereduced to about several hundreds of nanometers to several tens ofmicrometers right under the air curtain. That is, the cleaning solutionA 209 and cleaning solution B 211 are reduced to the slight amount inthe region in which the high-pressure dry airs 208, 210, 212 have passedin the semiconductor substrate 206. Therefore, thereafter, withoutthrowing off the cleaning solution by the high-speed rotation (=rotationspeed: about 1000 to 4000 rpm) as in the related-art method, at leastthe substantially equal effect of the drying treatment can be given tothe semiconductor substrate 206. In this case, since the physical load(=e.g., the centrifugal force, water current of the cleaning solution,and the like) is not applied to the semiconductor substrate 206, evenwith the use of the semiconductor substrate having a large bore diameter(e.g., the diameter of about 300 mm), it is possible to easily impartthe drying effect to the pattern of the photo resist without damagingthe pattern after the cleaning treatment.

In this manner, the present embodiment relates to the semiconductorsubstrate which has a large bore diameter (e.g., the diameter of about300 mm). Additionally, it is possible to obtain the equal or morecleaning effect as compared with the related-art method, that is, thehigh-speed rotating and cleaning of the semiconductor substrate.

It is to be noted that a nozzle 220 integrally constituted of the nozzlefor cleaning 202 and nozzle for developing 221 shown in FIG. 31 may alsobe used. As shown in FIG. 31, the nozzle 220 includes the nozzle forcleaning 202 and nozzle for developing 221. A discharge port 222 fordischarging the developing solution is formed in the slit shape in thenozzle for developing 221. The length of the direction of the dischargeport 222 crossing at right angles to the scan direction is equal to ormore than the maximum diameter or longest side of the substrate.Thereby, the developing solution can uniformly be supplied to the regionto be treated of the substrate continuously without being interrupted inthe direction substantially vertical to the scan direction. It is to benoted that the discharge port 221 forms the third discharge region. Itis to be noted that the position of the nozzle for developing 221 is notlimited to the front side of the nozzle for cleaning 202 with respect tothe scan direction as shown in FIG. 31. For example, the nozzle fordeveloping 121 may also be disposed on the rear side of the nozzle forcleaning 202 with respect to the scan direction.

With this nozzle, the developing treatment is not performed in parallelwith the cleaning treatment. At the developing treatment time, thenozzle for developing 221 discharges the developing solution, and thenozzle for cleaning 202 does not discharge the cleaning solution or jetout the gas. Moreover, at the cleaning treatment time, the nozzle forcleaning 202 discharges the cleaning solution and jets out the gas, andthe nozzle for developing 221 does not discharge the developingsolution.

As described above, in the first and second embodiments, as comparedwith the related-art cleaning method, it is possible to effectivelyperform the cleaning treatment of the substrates such as thesemiconductor substrate.

In the above, the semiconductor substrate has been described as oneexample of the substrate in the manufacturing steps of the semiconductordevice in the first and second embodiments. However, in theseembodiments, even with the use of the other substrates such as asubstrate for liquid crystal and mask substrate for exposure, thepresent invention is applied to the developing and cleaning treatments,and it is possible to enhance yield of each type of product.

Third Embodiment

FIG. 11 is a diagram showing a flowchart of a treating procedure of thedeveloping treatment method according to a third embodiment of thepresent invention. Moreover, FIGS. 12 to 16 are process diagrams showingthe treating procedure of the developing treatment method according tothe third embodiment of the present invention.

A developing method according to the third embodiment of the presentinvention will be described with reference to FIGS. 11 to 16.

(Step S101)

As shown in FIG. 12, a main surface of a substrate 300 including thesemiconductor substrate is coated with the resist of the chemicalamplification type (photosensitive resist film) via the reflectionpreventive film, and KrF excimer laser is used in the chemicalamplification type resist film to reduce/project/expose a circuitpattern via a reticle for exposure. The substrate 300 is subjected toPEB treatment. Subsequently, a transfer robot transfers the substrate300 into an upper part of a substrate holding portion 301 of adeveloping apparatus, and the substrate is sucked and fixed onto thesubstrate holding portion 301. At a rinsing time, and drying time, arotation mechanism 302 rotates the substrate 300 if necessary.

The developing apparatus according to the present embodiment furtherincludes a rinse nozzle 303, developing solution supply nozzle 304, andscan mechanism for scanning the developing solution supply nozzle 304from one end toward the other end of the substrate 300. The rinse nozzle303 discharges solutions having an oxidizing property or weak alkalisolutions, such as high-purity water, ozone water, and oxygen water viathe discharge port at a rinse time of the substrate 300 or at adevelopment stop time. The developing solution supply nozzle 304 has aside longer than the longest diameter of the substrate 300 and uniformlysupplies the developing solution to the substrate 300. It is to be notedthat the rinse nozzle preferably includes: a mechanism for rocking thedischarged cleaning solution; and an alleviation mechanism whichinhibits a force of the cleaning solution from being locallystrengthened inside the nozzle discharge port, in order to prevent thephotosensitive resist of the substrate main surface from being damagedby the discharged oxidizing solution or weak alkali solution, and allowthe cleaning solution to uniformly function on the substrate.

(Step S102)

Next, as shown in FIG. 13A, the rinse nozzle 303 is moved to apredetermined height from the substrate 300. While the substrate 300 isrotated by a rotation mechanism 302, an ozone water 306 having an ozoneconcentration of 5 ppm or less is discharged as a pretreatment solutionto the substrate 300 from the rinse nozzle 303 for about two seconds.During this, the rinse nozzle 303 moves on the main surface of thesubstrate 300, rocks the ozone water 306, and supplies the water ontothe substrate 300 main surface as uniformly as possible. Subsequently,as shown in FIG. 13B, the substrate 300 is rotated, and the substrate300 surface is dried.

Here, a pretreatment step is performed so as to uniformly form thesolution film on the substrate, but this pretreatment step is notnecessarily required. Moreover, an oxygen water, hydrogen water, nitricacid, oxygenated water, and alkali ion water may also be used as thepretreatment solution as long as the solution film can more uniformly beformed than by the ozone water.

(Step S103)

Subsequently, as shown in FIGS. 14A, 14B, as a first developingtreatment, the film of the developing solution which processes thephotosensitive resist film on the substrate 300 is formed on thesubstrate 300. Here, the linear developing solution discharge nozzle 304is scanned from one end to the other end of the substrate 300, adeveloping solution 307 is discharged in a curtain shape, and adeveloping solution film 307 is formed on the substrate 300. As shown inFIG. 14B, since the length of the developing solution supply nozzle 304in a direction vertical to the scan direction is longer than thediameter of the substrate 300, the film of the developing solution 307can be formed on the whole surface of the substrate 300.

A developing solution film forming step is not limited to the methoddescribed herein. For example, as shown in FIGS. 15A, 15B, there is amethod comprising: supplying the developing solution from the lineardeveloping solution supply nozzle 304 while rotating the substrate 300to form the developing solution film 307 in the whole surface of thesubstrate 300. FIG. 15 is a diagram showing a modification example ofthe developing solution film forming method according to the thirdembodiment of the present invention. FIG. 15A is a sectional view, andFIG. 15B is a plan view.

Moreover, as shown in FIGS. 16A, 16B, there is a method comprising:supplying the developing solution 307 to the substrate 300 from astraight tubular nozzle 312 while rotating the substrate 300 to form thedeveloping solution film 307 in the substrate 300 whole surface. Inaddition to the methods described herein, various modes may be used.FIGS. 16A, 16B are diagrams showing the modification example of thedeveloping solution film forming method according to the thirdembodiment of the present invention. FIG. 16A is a sectional view, andFIG. 16B is a plan view.

(Step S104)

A first cleaning treatment comprises: discharging the pure water fromthe rinse nozzle 303 in about five seconds after the developing solutionfilm is formed in the substrate main surface and simultaneously rotatingthe substrate; and washing away the developing solution film from thesubstrate 300. Subsequently, while rotating the substrate 300 at a lowspeed, the low-concentration ozone water was discharged.

(Step S105)

Subsequently, the substrate 300 was rotated at the high speed, and thesubstrate 300 surface was dried.

The method may also comprise: discharging the low-concentration ozonewater from the rinse nozzle 303 and simultaneously rotating thesubstrate; cleaning the substrate by the low-concentration ozone waterfor about ten seconds; substantially rotating the substrate at the highspeed; and drying the substrate.

In the present embodiment, as the cleaning solution having the oxidizingproperty, the ozone water was used having the low concentration to suchan extent that the resist does not suffer a damage not less than anallowable range. If the similar effect is produced, the oxygen waterobtained by dissolving oxygen in the pure water may also be used as thecleaning solution having the oxidizing property. Furthermore, if thesimilar effect is produced, and the resist does not suffer the damagenot less than the allowable value, the weak alkali aqueous solution mayalso be used.

(Step S106)

Next, a second developing treatment comprises: forming the developingsolution which processes the resist film on the substrate 300 on thesubstrate 300. Here, the method comprised: scanning the lineardeveloping solution discharge nozzle from one end to the other end ofthe substrate; and discharging the developing solution in the curtainform to form the developing solution film on the substrate.

The developing solution may also be agitated on the substrate mainsurface in the middle of the second developing treatment if necessary.In this case, examples of an agitating method of the formed developingsolution film include: a method of disposing a rectifier plate on thesubstrate and rotating the rectifier plate to generate an air current; amethod of rotating the substrate itself; and a method of vibrating thesolution by an vibrator from the outside. Any method may also be used ifthere is a function of fluidizing the developing solution in thesubstrate whole surface.

(Step S107)

A second cleaning treatment comprised: discharging the pure water fromthe rinse nozzle 303 in about 25 seconds after forming the developingsolution film in the substrate 300 main surface while rotating thesubstrate 300 at 500 rpm. It is to be noted that the pure water was usedas the cleaning solution after the second development in the presentembodiment. However, if a higher cleaning effect is produced anycleaning solution may also be used such as a reducing solution,oxidizing solution (ozone water, oxygen water), weak alkali ion water,slightly acidic ion water, supercritical water, carbonated water,hydrogen water, and pure water. Moreover, it is also possible toappropriately combine these solutions if the cleaning effect is raised.

(Steps S108, S109)

After rotating the substrate at the high speed and drying the substrate,the developing step is ended and the substrate is recovered by thetransfer robot.

A problem and cause of the related-art developing method will bedescribed. For the photosensitive resist of the chemical amplificationtype, a fine alkali soluble region and alkali hardly soluble region areformed in the resist film by exposure and heat treatment of a desiredpattern. When these alkali soluble and alkali hardly soluble regionscontact the alkali developing solution, the alkali soluble region isdissolved in alkali and the alkali hardly soluble region is notdissolved in a time required for a conventional developing step of ausual KrF resist. The reaction product generated from the alkali solubleregion during the development is held between the resist patterns whichare alkali hardly soluble region, receives interaction among moleculesfrom the resist hardly soluble region and similarly dissolved reactionproduct, and remains in position. Especially, when the processeddimension becomes fine, the resist pattern dimension also becomes fine.Therefore, the dimensions of the alkali soluble and hardly solubleregions are also reduced, the interaction among the molecules becomesstrong, and the molecules are not easily diffused into the atmosphere inthe solution. Moreover, a binding force acts so that the reactionproduct remains in position by an electrostatic potential from thesubstrate even after the dissolution. As a result, alkali ions areinhibited from being further diffused into the soluble resist region,alkali concentration differs with positions in the vicinity of theresist surface, the development is inhibited, and the developing ratechanges with the positions.

The developing solution was unmovably mounted on the substrate, thedeveloping solution on the substrate was replaced with the cleaningsolution (pure water) immediately after elapse of a predetermined time,and the development was stopped. In this method, local retention of thereaction product occurs in the substrate plane as described above, andthe product is not removed until the development ends. Therefore, thedevelopment is inhibited, and a difference is generated in thedeveloping rate in the plane. Since the developing rate changesespecially in accordance with the amount of the reaction products, theamount of generated reaction products differs in coarse and denseregions of the pattern. This causes a phenomenon in which the alkali ionconcentration differs in the vicinity of the resist in the patterncoarse and dense regions. That is, a phenomenon occurs in which thedeveloping rate differs in the vicinity of the resist surface in thepattern coarse and dense regions. As a result, a problem of coarse/densedifference of the dimension is generated in the resist pattern.

To solve the problem, a method has been considered comprising: removingthe reaction product once in the middle of the development and using afresh developing solution to perform the development again. However, themethod of performing the development in two divided steps is a knowntechnique, and this is described, for example, in Jpn. Pat. Appin. KOKAIPublication No. 2-46464. In the Jpn. Pat. Appin. KOKAI Publication No.2-46464, after the development is performed with the developing solutiononce, the rinsing/drying is performed, and the development is performedagain in the highly dense developing solution. The inventor has foundthat resist residual and scum in the bottom portion of the resistpattern are thereby removed. These residual and scum are non-dissolvedportions of the resist, and are not the reaction products generated bythe development which are objects to be removed in the cleaning afterthe first development. These residual and scum in the resist bottomsurface are so-called significant points which have a possibility offorming defects after the development, and do not substantiallycontribute to the uniformity in the plane. Therefore, the problem in therelated-art development is not solved in the Jpn. Pat. Appin. KOKAIPublication No. 2-46464. Moreover, as not especially described, in thiscase, the rinse solution usually indicates the pure water. This respectis a large difference from the method described in the presentembodiment.

In general, when the pure water is used to clean the substrate in thefirst cleaning treatment after the first development, the developingsolution having high pH is replaced with the pure water of pH7, a rapidpH change is generated in the resist surface, and an alkali hardlysoluble layer is formed. Therefore, in the second development of thepattern from which the reaction product is clearly removed, dissolutionby alkali uniformly starts from this hardly soluble layer. The surfaceshape of the hardly soluble layer finally formed when the firstdevelopment shifts to the cleaning is reflected and left. On the otherhand, the hardly soluble layer formed during the replacement of thedeveloping solution with the cleaning solution strongly reflectsinfluences such as exposure amount dispersion or focus dispersion at anexposure time and developing rate dispersion in initial development. Ingeneral, uniformity is bad. Therefore, the dimensional uniformity in thesubstrate plane of the resist pattern formed after the development isdeteriorated as compared with usually only one development. Therefore,it has been seen that the problem by the related-art developing methodis not solved and additionally the dimensional uniformity in thesubstrate plane is deteriorated in the method of the Jpn. Pat. Appin.KOKAI Publication No. 2-46464.

The developing method described in the present embodiment ischaracterized in that the treatment is performed by the solution havingthe oxidizing property such as the ozone water between the first andsecond developing treatments. When the cleaning is performed first withthe pure water and subsequently with the ozone water, the surface hardlysoluble layer formed in contact with the pure water from the developingsolution is treated with the ozone water, and thereby the surface isoxidized and changed in properties. Alternatively, the ozoneconcentration is slightly raised, the surface is slightly decomposed,and the hardly soluble surface becomes soluble to alkali. On the otherhand, when the ozone water is used from the beginning to perform thecleaning, ozone molecules easily enter and oxidize the resist surfaceswelling with the developing solution. Therefore, even when pH drops,the resist surface is not substantially hardly-soluble, and keepssolubility to alkali. In any case, when the second development issuccessively performed, regardless of the first development, an image isdeveloped faithfully to an optical profile at an exposure time to formthe resist pattern. Furthermore, when the developing time hassubstantially the same length as the related-art developing time, thedevelopment sufficiently proceeds without being influenced by thereaction product or surface hardly soluble layer. Therefore, theinfluences of the exposure amount at the exposure time and focusdispersion are alleviated, and the dimensional uniformity in the planeof the resist pattern after the development. Moreover, by the cleaningwith the oxidizing solution such as the ozone water, the reactionproduct existing between non-formed resist patterns is decomposed andcan clearly be removed. Furthermore, it is also possible to remove theparticles which could form defects after the development.

Moreover, a time for which the first cleaning solution is dischargedfrom the first development is set to about five seconds in the presentembodiment, and reasons for this are as follows.

FIG. 17 schematically shows a graph of a reflected light intensity totime, obtained during observation of a state of dissolution of a KrFpositive resist film by the developing solution. A sinusoidal wave seenin a first stage in FIG. 17 graph is an interference effect by a filmthickness caused because the development proceeds in a depth directionof the film thickness. In general, for the resist, in this first stageimmediately after development start, as shown in FIG. 18A, a dissolutionrate is high in the soluble regions of exposed portions 331 of a resistfilm 330, the dissolution proceeds in the depth direction, and thepositive resist for DUV exposure requires about five to ten secondsuntil the dissolution goes through the bottom surface of the resist. Ina second stage, as shown in FIG. 18B, the development proceeds in adirection in which a resist pattern side wall is dissolved, not in thedepth direction of the resist film thickness. At this time, reflectionintensity slowly changes. In this second stage, the dissolution ratedrops, the side wall of the resist pattern is dissolved to a desireddimension, and therefore the dissolution direction proceeds in arelatively horizontal direction.

In this manner, the dissolution of the resist proceeds in the depthdirection in the first stage, and proceeds in a transverse direction inthe second stage. This is because an exposure intensity slowly changesto a non-exposed portion from the exposed portion by an exposureintensity distribution by diffraction of unavoidable light in exposureof a projection type. By the distribution of the exposure intensity, amiddle portion between the patterns which has a intense exposure amount,that is, which is sufficiently exposed comes off fastest at thedevelopment time. Therefore, the development rapidly proceeds in thedepth direction as in the first stage. On the other hand, the developingrate is slow in the vicinity of the pattern wall whose exposure amountis small as compared with the middle portion. Therefore, the developmentslowly proceeds in the transverse direction as in the second stage. Mostof dissolving materials which inhibit the development usually in thedevelopment are generated in this first stage.

In the present embodiment, the time for which the first cleaningsolution is discharged from the first developing treatment is set toabout five seconds after the development start. This is a position wherethe first stage switches to the second stage, that is, where thedevelopment proceeds in a reverse dir in the dissolved portion and goesthrough the bottom surface of the resist. This timing has the followingreason.

The dissolution product generated once in this first stage is washedaway during the change to the second stage from the first stage, and thealkali concentration can thereby be prevented from dropping by thedissolution product which inhibits the development from proceeding. Ifthe first development is stopped earlier, the dissolution product isgenerated again in the next development stage to lower the alkaliconcentration, and inhibits the development. If the stop time of thefirst development is retarded, the alkali concentration locally drops bythe generated dissolution product, and the developing rate locally dropsin the development of the second stage. Thereafter, even if thedevelopment is performed with the fresh developing solution again, firstformed spatial non-uniformity is not solved. By the first developmentstop time retarded from the time of the change to the second stage fromthe first stage, the local alkali concentration drop increases for eachposition, and the non-uniformity is also amplified.

The soluble region which is dissolved in the second stage and whichremains in the vicinity of the pattern side wall has a low dissolutionrate in the development. Moreover, the cleaning is performed once in thefirst stage, and thereafter the dissolution product which can vary thealkali concentration related to the development in time/space is alreadyremoved and hardly generated. Therefore, a pattern line width cansufficiently be controlled in the second development.

For the above-described two reasons, it is optimum to set a first timingof development stop to a change time between the first and secondstages.

In the present embodiment, a point at which the first stage changes tothe second stage in FIG. 17 was five seconds. This value changes by aresist material, developing solution, alkali concentration, temperature,and the like, and is not limited to the value of the present embodiment.

Next the effect of the present embodiment will be described based on theresult of an experiment actually performed by the present inventors.

A wafer was successively coated with the reflection preventive film andKrF positive resist, and the reticle including the pattern constitutedof a line and space each having a width of 200 nm (200 nmL/S pattern;L:S=1:1) and a pattern constituted of a line with a width of 200 nm andspace with a width of 2000 nm (200 nm isolated line; L:S=1:10) was usedto perform reduction/projection/exposure in the KrF excimer laser. Afterthe heat treatment step, the developing treatment was performed. In thedeveloping treatment step, four types of samples were prepared asfollows. Conditions are shown in Table 1.

TABLE 1 Sample for Sample A Sample B Sample C reference PretreatmentOzone Ozone Ozone Ozone water water water water First developing PresentPresent Present Present treatment First cleaning Water Ozone Purewater + Absent treatment water ozone water Second Present PresentPresent Absent developing treatment

For all the wafers of the samples, pretreatment was performed with theozone water, the developing solution supply amount from the developingsolution supply nozzle was set to 1.5 L/min, the scanning speed of thenozzle was set to 60 mm/sec, and the developing solution film having asolution thickness of 1.5 mm was formed (first developing treatment).For a sample for reference, the subsequent first cleaning treatment andsecond developing treatment were not performed, and the developingsolution film was formed once. Sample A was once cleaned with water infive seconds after the development start (first cleaning treatment), thedeveloping solution supply amount from the developing solution supplynozzle was set to 1.5 L/min again, the scanning speed of the nozzle wasset to 60 mm/sec, and the solution film having a solution thickness of1.5 mm was formed (second developing treatment).

On the other hand, Sample B was subjected to the first cleaningtreatment with the ozone water, and Sample C was subjected to the firstcleaning treatment with the pure water. Thereafter, the samples weresuccessively cleaned with the ozone water. Furthermore, a seconddeveloping solution film was formed in the same manner as in Sample A(second developing treatment). The subsequent second cleaning treatmentand drying treatment were all performed on the same conditions.

Dimension evaluation results of these samples are shown in Table 2.

TABLE 2 Sample for Sample A Sample B Sample C reference 1:1 pattern 12.26.5 5.8 6.1 uniformity 3σ [nm] 1:10 pattern 15.2 8.2 7.8 8.3 uniformity3σ [nm] Coarseness/ 20 5 7.8 30 denseness [nm]

Table 2 shows a dimension difference of the lines of the 200 nmL/Spattern and 200 nm isolated line pattern on the same substrate as acoarse/dense difference. The coarse/dense difference in Table 2 is avalue obtained by subtracting the dimension of the L/S pattern (1:1pattern) from that of the isolated line pattern (1:10 pattern).

In the reference sample, the in-plane uniformity of the patterndimension is relatively satisfactory. However, after the developingsolution film is formed, the reaction product hardly moves. Therefore,the isolated line pattern (1:10 pattern) whose reaction region per unitarea is large is thicker than the L/S pattern (1:1 pattern) whosereaction region per unit area is small by a dimension of 30 nm.

On the other hand, in Sample A the coarse/dense difference is slightlysolved. On the other hand, the uniformity in the plane is largelydeteriorated. Causes for these are considered as follows. First, areason for a small coarse/dense difference is considered as follows. Theamount of the reaction product existing usually in the vicinity of thepattern locally differs in coarse/dense portions of the resist pattern,and a local difference is also generated in the alkali ion concentrationin the developing solution. However, the developing solution is oncereplaced with the pure water, and the fresh concentration developingsolution is supplied again. Therefore, this local difference of thealkali concentration is eliminated. Therefore, regardless of thecoarse/dense pattern, the development is promoted by the freshdeveloping solution, the image is developed faithfully to the originaloptical profile, and therefore the dimensional difference generated bythe coarse/dense pattern is slightly reduced.

The problem of the dimensional uniformity in the plane is considered asfollows. In general, the dissolution rate is high in a stage in whichthe developing time is short. In the stage in which the developing timeis short, for example, when the exposure amount and exposure focusdiffer by the position on the wafer, the difference of the dissolutionrate more remarkably appears. Since the development is usually performedin a sufficiently long time, this phenomenon is not seen. However, inthe present embodiment the first rinse solution is discharged in thestage in which the developing time is short, and the first developmentstops. Therefore, the above-described effect is supposed to remarkablyappear. Moreover, at this time, the pure water is applied in the middleof the actively occurring development reaction, rapid pH value changeoccurs, and the resist component coagulates in an interface between theresist and pure water. Especially the portion to be originallydissolved, such as the resist surface of the non-dissolved portionincluding the pattern side wall, is hardly soluble. Thereafter, thedeveloping solution is again mounted, thereby the development isperformed again, but the surface of the resist of the region where thedissolution originally proceeds coagulates by the contact with the purewater, and the solubility drops. Therefore, the shape of the hardlysoluble layer formed by the contact with the pure water, not theoriginal latent image, is reflected and the dissolution proceeds.Therefore, the bad uniformity at a time when the cleaning is performedin short time is maintained, and the development proceeds. As describedabove, the influence of the development inhibition caused by thereaction product by the development is eliminated, the coarse/densedifference thereby drops, but factors which largely influence theinitial development such as the exposure amount or focus vibration exertthe larger influence, and deteriorate the uniformity in the plane.

On the other hand, in Samples B and C, the uniformity in the wafer planeis enhanced to be equal to or more than that of the sample forreference. This is because the resist once brought in contact with thepure water coagulates, the hardly soluble layer is formed in thesurface, but the ozone water is added to oxidize the hardly solublelayer in the resist surface of the non-dissolved portion such as theside wall of the pattern, and the solubility to the developing solutionis in a maintained state. Therefore, when the fresh concentrationdeveloping solution is added again, the development is not inhibited bythe surface hardly soluble layer of the resist by the pattern side wall,the phenomenon is successively promoted, and the dimensional uniformityin the plane is enhanced.

Moreover, the effect that the reaction product in the vicinity of theresist pattern is washed away by performing the rinsing once is the sameas that of Sample A described above. When the second fresh developingsolution is supplied, the local developing solution alkali concentrationdrop is not caused by the reaction product and is uniform, and thereforethe coarse/dense difference of the dimension can largely be reduced.

Here, a reason why the uniformity of Sample B is slightly different fromthat of Sample C is that Sample B is cleaned all with the ozone water inthe first cleaning treatment, the coagulation of the resist component inthe rapid pH value change at a change time to the rinse solution fromthe developing solution is alleviated by the ozone water, andadaptability of the resist surface with respect to the developingsolution is kept as such.

It is to be noted that the above-described first developing treatment,first cleaning treatment, second developing treatment, and secondcleaning treatment can be performed using the apparatus shown in FIG. 30or 31. The treatment performed using the apparatus shown in FIG. 30 willbe described. At a first and second developing treatment time, while thedeveloping solution is supplied onto the substrate from the nozzle fordeveloping 121, the nozzle 220 is scanned/moved on the substrate. At afirst cleaning treatment time, while the ozone water is supplied ontothe substrate from the cleaning solution supply nozzle 102 a, the nozzle220 is scanned/moved on the substrate. At a second cleaning treatmenttime, the treatment is performed in the same manner as in the methoddescribed in the first embodiment.

The treatment performed using the apparatus shown in FIG. 31 will bedescribed. At the first and second developing treatment time, while thedeveloping solution is supplied onto the substrate from the nozzle fordeveloping 121, the nozzle 220 is scanned/moved on the substrate. At thefirst cleaning treatment time, while the dry air is supplied from thefirst air supply nozzle 202 a and the ozone water is supplied onto thesubstrate from the cleaning solution supply nozzle 102 a, the nozzle 220is scanned/moved on the substrate. At the second cleaning treatmenttime, the treatment is performed in the same manner as in the methoddescribed in the second embodiment.

Fourth Embodiment

FIG. 19 is a diagram showing a flowchart of the development treatingprocedure according to a fourth embodiment of the present invention.

Since steps S201 to S203 are similar to the steps S101 to S103 describedin the third embodiment, the description thereof is omitted.

(Steps S204, S205)

The low-concentration ozone water was discharged from the rinse nozzlein about five seconds after the developing solution film was formed inthe substrate main surface in step S203. Subsequently, the substrate wasrotated, and almost all the cleaning solution was removed, but withoutdrying the substrate, the cleaning solution was slightly left, and theozone water film was formed.

(Step S206)

Subsequently, the developing solution for processing the resist film onthe substrate was formed on the substrate in which the ozone water filmwas formed. The forming method of the developing solution film issimilar to that of the third embodiment.

Since steps S207 to S209 are similar to the steps S107 to S109 describedin the third embodiment, the description thereof is omitted.

The developing step of the present embodiment has substantially the samefunction as that of the third embodiment. In the present embodiment, thesolution having the oxidizing property or weak alkali solution is lefton the substrate main surface, and thereby the affinity of thedeveloping solution to the substrate surface at the second developingtreatment time is enhanced. Thereby, when the developing solution issupplied, a repulsive force acting between the developing solution andsubstrate surface is reduced, the developing solution can uniformly besupplied in the substrate plane, and as a result the in-plane uniformityof the dimension after the development is enhanced.

From the first cleaning treatment to the second developing treatment inthe developing step, after the first cleaning treatment, the substratewas rotated at 500 rpm for ten seconds without being rotated at the highspeed, and successively the second developing solution was discharged.The experiment was performed on conditions similar to those of Sample Cof the third embodiment excluding the above-described respect. Resultswere 6.1 nm with the 1:1 pattern uniformity 3σ, and 7.5 nm with the 1:10pattern uniformity 3σ, and the coarse/dense difference was 5 nm. Theseare sufficiently good values as compared with the sample for reference.

Fifth Embodiment

In the present embodiment, since the procedure of the development stepis similar to that of the third embodiment, detailed description isomitted. In the present embodiment, at the first and second developingtreatment time, gas molecules having the oxidizing property such asoxygen, or gas molecules having the reducing property such as hydrogenare dissolved in the developing solution.

A treatment apparatus for use in the present embodiment is shown in FIG.20. As shown in FIG. 20, the present apparatus includes: a developingsolution tank 401 in which the developing solution including thealkaline aqueous solution is stored; a dissolution film 402 connected tothe developing solution tank 401 via a pipe; a oxidizing gas generator403 and reducing gas generator 404 connected to the dissolution film 402via pipes; and the developing solution supply nozzle 304 connected tothe dissolution film 402 via the pipe. Moreover, a protective cover isdisposed around the substrate 300. It is to be noted that the samecomponents as those of the developing apparatus shown in FIG. 12 aredenoted with the same reference numerals and the description thereof isomitted.

In the present apparatus, the gas generated by the oxidizing gasgenerator 403 or reducing gas generator 404 is dissolved in thedissolution film 402, the developing solution supplied from thedeveloping solution tank 401 is passed through the dissolution film 402,and the oxidizing or reducing gas is dissolved in the developingsolution. In this apparatus, the oxidizing gas (reducing gas) can bedissolved in the developing solution immediately before the developingsolution is discharged to the substrate 300.

In the present embodiment, the oxygen gas which was the oxidizing gaswas dissolved in the developing solution to perform the first and seconddeveloping treatments. Since the other treatments are similar to thoseof the third embodiment, the detailed description is omitted.

It is to be noted that the developing solution with the oxygen moleculesdissolved therein was used in the first and second developingtreatments, but the developing solution with the reducing gas moleculessuch as hydrogen molecules dissolved therein may also be used. Moreover,if the effect is sufficient, it is not necessary to use the developingsolution with the oxidizing gas molecules dissolved therein at both thefirst and second developing treatment times, and the solution may beused at either one treatment time.

In the present embodiment, in addition to the function described in thethird embodiment, the solution in which the oxidizing gas molecules aredissolved is used as the developing solution to perform functionsincluding: the oxidizing of the reaction product generated immediatelyafter the development start by the oxygen molecules in the developingsolution and the decomposing of the reaction product; the oxidizing ofthe resist surface in the developing solution; and the alleviation ofsize growth by coagulation of the reaction product generated during thedevelopment.

Moreover, when the developing solution with the reducing gas moleculesdissolved therein is used at both or either of the first and seconddeveloping treatment times, there are functions such as: the changing ofthe properties of the resist surface by reducing electrons; promotion ofdiffusion of the reaction product into the developing solution by asurface potential change of the reaction product; and the prevention ofadhesion of the reaction product again to the resist surface by thechange of the resist surface potential.

At the first and second developing treatment times, the developingsolution in which the oxidizing gas molecules were dissolved was used toperform an experiment similar to that of the third embodiment. Theexperiment results were 3.8 nm with the 1:1 pattern dimensionaluniformity of 3σ, and 6.1 nm with the 1:10 pattern, and anticipatedeffects were confirmed.

Sixth Embodiment

FIG. 21 is a diagram showing a flowchart of the development treatmentaccording to a sixth embodiment of the present invention.

Since the procedure in the pattern treating method of the presentembodiment is similar to that of the third embodiment, illustration ofthe flowchart and detailed description of the procedure are omitted.

In the present embodiment, at the first developing treatment time, afterforming the developing solution film, the development is performed whilethe substrate is in a stationary state. Subsequently, after the elapseof a predetermined time, as shown in FIG. 22, the substrate 300 isrotated at a predetermined revolution number, and the developingsolution 307 is fluidized. After rotating the substrate for thepredetermined time and fluidizing the developing solution, the substrateis again stopped, and the exposure is performed in the stationary state.

In the present embodiment, a time zone in which the developing solutionis fluidized is determined as follows.

As described in the third embodiment, the development is constituted of:the first stage in which the development proceeds in the depth directionof the film thickness; and the second stage in which the developmentproceeds in the direction for dissolving the resist pattern side wallafter the first stage.

A purpose of the fluidizing of the solution in the developing step liesin that the reaction product generated during the development isuniformed, and alkali concentration is recovered. Therefore, thesolution may effectively be fluidized so as to include a time to switchto the second stage in which the reaction product is hardly generatedafter the first stage in which a large amount of reaction product isgenerated (this time will hereinafter be referred to an off time).

Next, a way to determine the off time will be described. It is to benoted that the method of determining the off time described hereinaftermay also be used to determine a start timing of the first cleaningtreatment described in the third embodiment.

A first method comprises: allowing a light to be incident upon thepattern which is an object; measuring a change of the reflected lightintensity obtained by reflection; obtaining results as shown in FIG. 17;and obtaining the off time. At this time, for the reflected lightintensity of FIG. 17, a reflected light having a single wavelength ismore preferable. Therefore, the incident light is set to the singlewavelength using a narrow band filter, or a measured reflected light maybe split. The off time may be measured before the development isactually performed, or may be measured in the developing step withrespect to each substrate.

As a second method, there is a method of: developing the pattern whichis an object in a plurality of developing times; observing the sectionalshape of the pattern after the development; and obtaining a time inwhich the resist of the soluble region is developed to the bottomsurface. Next, the measurement of the off time will be described basedon two experiment results.

A first experiment object pattern was set to a 130 nmL/S(1:1) pattern(reflection preventive film having a film thickness of 60 nm, resistwith a film thickness of 300 nm, and resist whose dissolution rate isrelatively high). First, the reflected light intensity during thedevelopment of the object pattern shown in FIG. 23 was acquired. Thereflection intensity indicates a result of a case in which a light witha wavelength of 550 nm was incident. From this result, the off time ofsix seconds was obtained, and the time to fluidize the solution wasdetermined based on this value.

A diagram in which a flow of development start, developing solutionflow, and development end is shown along a time axis is shown in FIG.24. After a developing solution supply step, stationary development isperformed for (x-1) seconds. Thereafter, the substrate was rotated at apredetermined revolution number (250 rpm) for two seconds, and thedeveloping solution was fluidized. The development was stopped in 30seconds after the development start. At this time, x was defined as thetiming to fluidize the solution. The dispersion (3σ) of 130 nmL/S(1:1)pattern with a change of x in two to 12 seconds is shown in FIG. 25. Thedispersion without fluidizing any solution is 10.2 nm. Since thesolution was fluidized, the dispersion decreased. Especially, bestuniformity was obtained with six seconds. Moreover, the uniformity wasrelatively good with four, eight seconds. That is, with the solutionflow in the vicinity of the off time obtained from the reflected lightintensity change of the object pattern (off time ±two seconds, that is,off time ±33%), good uniformity is obtained.

It is obvious from the experiment that the timing of to fluidize thesolution is set in the vicinity of the off time (time in which theresist of the soluble region is developed to the bottom surface) and theuniformity is enhanced. However, when the solution fluidizing start timecan be set only after the off time because of restrictions of theapparatus such as the movement of the developing solution supply nozzle(e.g., when the substrate cannot be rotated in and after nine seconds),the solution may be fluidized as early as possible (e.g., nine seconds).

A second experiment object pattern was set to the 130 nmL/S(1:1) pattern(reflection preventive film having a film thickness of 60 nm, resistwith a film thickness of 300 nm, and resist whose dissolution rate isrelatively low). First, the reflected light intensity during thedevelopment of the object pattern shown in FIG. 26 was acquired. This isa result of the case in which the light with a wavelength of 550 nm wasincident. From this result, the off time of 20 seconds was obtained, andthe time to fluidize the solution was determined based on this value.

A diagram in which a sequence is shown along the time axis is shown inFIG. 24. After the developing solution supply step, the stationarydevelopment was performed for (x-1) seconds. Thereafter, the substratewas rotated at the predetermined revolution number (250 rpm) for twoseconds, and the developing solution was fluidized. The development wasstopped in 60 seconds after the development start. At this time, x wasdefined as the timing to fluidize the solution. The dispersion (3σ) ofthe 130 nmL/S(1:1) pattern with a change of x in ten to 35 seconds isshown in FIG. 27. The dispersion without fluidizing any solution is 9.8nm. Since the solution was fluidized, the dispersion decreased.Especially, best uniformity was obtained with 20 seconds. Moreover, theuniformity was relatively good with 15, 25 seconds. That is, with thesolution flow in the vicinity of the off time obtained from thereflected light intensity change of the object pattern (off time ±fiveseconds, that is, off time ±25%), good uniformity was obtained.

In the present embodiment, a method of rotating the substrate has beendescribed as the method of fluidizing the solution. Any method may beused as long as the developing solution is fluidized, such as a methodof forming an air current in the surface of the developing solution filmto fluidize the developing solution; a method of bringing a material forcausing the flow in contact with the developing solution on thesubstrate or moving the material or substrate to fluidize the developingsolution; a method of vibrating the substrate to which the developingsolution is supplied to fluidize the developing solution; and a methodof heating a material to be treated to fluidize the developing solutionby convection.

Moreover, in the present embodiment, the L/S pattern is used as theobject pattern, but any pattern may also be used such as an isolatedremaining pattern, isolated through pattern, hall pattern, and pillarpattern. For each pattern, after the off time is obtained, the timing tofluidize the solution may be determined. When a plurality of patternsare included at the same time (e.g., the isolated remaining pattern andL/S pattern), the solution may be fluidized twice after each off time,and the timing to fluidize the solution may also be determined from theoff time of only the pattern having strict precision.

A large number of proposals to fluidize the developing solution havebeen reported. Examples of the proposals include: a method comprisingsupplying the developing solution onto the substrate, forming the aircurrent so as to contact the surface of the developing solution film,holding the developing solution film on the substrate to form the flowof the surface, and fluidizing the developing solution (Jpn. Pat. Appin.KOKAI Publication No. 2001-228625); a method of bringing a tip end ofthe nozzle for supplying the developing solution in contact with thedeveloping solution on the substrate, and moving the nozzle or substrateto fluidize the developing solution (Jpn. Pat. Appin. KOKAI PublicationNo. 2000-195773); and a method of vibrating the substrate to which thedeveloping solution has been supplied at a predetermined frequency tofluidize the developing solution (Jpn. Pat. Appin. KOKAI Publication No.2001-307994). However, in any proposal, the timing to fluidize thesolution after the developing solution supply is not described. As aresult, since the solution is not fluidized in an appropriate time zone,the solution cannot effectively be fluidized, and the sufficientdimensional uniformity was not obtained.

Seventh Embodiment

In the semiconductor manufacturing process, an operation ofpaddle-forming the developing solution on the substrate in which theresist film is formed, and processing the resist film in a desired shapeis repeatedly performed. In the related art, the substrate in which theresist film is formed has heretofore been coated with the developingsolution to perform the developing step. In general, the developingsolution supply nozzle is used to supply the developing solution. In thedeveloping method in which the developing solution supply nozzle is usedin this manner, the tip end of the nozzle from which the developingsolution is discharged is positioned in the vicinity of the substrate,and the solution is supplied. Therefore, the developing solution inwhich the resist is dissolved contacts the nozzle. As a result, a solidmaterial of the resist sticks to the developing solution supply nozzle.This sticking material sometimes causes the defect of the substrate.

As means for solving this problem, the nozzle is cleaned by thedeveloping solution, or the nozzle is cleaned by a high-concentrationdeveloping solution (Jpn. Pat. Appin. KOKAI Publication No.2001-319869). In these methods, since the developing solution is used asthe cleaning solution, only the defect soluble to the developingsolution can be removed. Moreover, the use of the developing solutionraised a problem of cost increase.

FIG. 28 is a flowchart showing a treating procedure of a pattern methodaccording to a seventh embodiment of the present invention. FIG. 29 is aschematic diagram of a constitution of the developing apparatusaccording to the third embodiment of the present invention. Moreover,the development treating method according to the third embodiment of thepresent invention will be described with reference to FIGS. 28 and 29.

(Step S401)

The substrate is coated with the reflection preventive film and theresist of the chemical amplification type, and the KrF excimer laser isused to reduce/project/expose a desired pattern via the reticle forexposure. The substrate is heat-treated, transferred to the upper partof the substrate holding portion by the transfer robot, and sucked andfixed onto the substrate holding portion.

(Step S402)

Next, ozone generated by an oxidizing gas generator 504 is supplied to adissolution film 503, the pure water is supplied to the dissolution film503 from a pure water source 502, and ozone is dissolved in the purewater and generated. Subsequently, the generated ozone is supplied tothe developing solution supply nozzle 304. When the developing solutionsupply nozzle 304 discharges the ozone water, the developing solutionsupply nozzle 304 is cleaned. The ozone water discharged from thedeveloping solution supply nozzle 304 is received by a solution receiver505, and the ozone water is pooled in the solution receiver 505. Whenthe developing solution supply nozzle 304 is immersed in the ozone waterpooled in the solution receiver 505, the surface of the developingsolution supply nozzle 304 disposed opposite to the resist film iscleaned.

After cleaning the developing solution supply nozzle 304, the developingsolution is supplied to the developing solution supply nozzle 304 from adeveloping solution tank 501, the developing solution is discharged fromthe developing solution supply nozzle 304, and the ozone water in thenozzle is replaced with the developing solution.

It is to be noted that when the oxidizing gas can be line-supplied, theoxidizing gas generator 504 is unnecessary. Moreover, in addition toozone, oxygen, carbon monoxide, and hydrogen peroxide may also be usedas the oxidizing gas.

(Step S403)

Next, the developing solution film which processes the resist film onthe substrate is formed on the substrate. Here, the linear developingsolution supply nozzle is used to supply the developing solution whilethe nozzle is scanned from one end to the other end of the wafer to formthe developing solution film on the substrate.

(Step S404)

After a predetermined time, the rinse solution (e.g., pure water) issupplied from the rinse nozzle disposed above the substrate, and thesubstrate is rotated/cleaned.

(Step S405)

Furthermore, the substrate is rotated at the high speed to throw off thepure water, and the substrate is dried.

In the present embodiment, the ozone water in which ozone is dissolvedin the pure water is used as the oxidizing solution, but gas moleculesto be dissolved are not limited to ozone as long as the similar effectis obtained. For example, the oxidizing gases such as oxygen, carbonmonoxide, and hydrogen peroxide may also be used. Moreover, the nozzleis cleaned before supplying the developing solution in the presentembodiment, but may also be cleaned after the developing solutionsupply. Furthermore, each substrate does not have to be cleaned, andevery predetermined number of substrates may be cleaned, or thesubstrate may be cleaned for each predetermined time. Moreover, thecleaning may also be performed after maintenance such as the change ofthe nozzle.

When the developing treatment is repeated, the developing solutionsupply nozzle contacts the developing solution with the resist dissolvedtherein, and thereby the organic particles stick to the nozzle. In thesubsequent developing treatment of the substrate, the particles stick tothe resist surface, and has a possibility of remaining as the defect.

During the cleaning, the ozone molecules in the solution collide againstthe particles sticking to the nozzle, oxidize the particles at a certainprobability, and are supposed to decompose the particles. The decomposedparticles form low molecules, the mass is sufficiently reduced, and theparticles are easily diffused into the solution. As a result, theparticles are removed.

The result of the experiment actually performed by the inventors will bedescribed hereinafter.

The experiment was performed following the procedure shown in theflowchart of FIG. 28. To confirm the effect, in step S402, the number oforganic matter sticking defects were measured, when the nozzle wascleaned with the ozone water having an ozone concentration of 10 ppm inthe solution for five seconds, when the nozzle was cleaned with thedeveloping solution for five seconds, and the nozzle was not cleaned. Inthe respective cases, the number of defects was five, ten, 50 defects.When the nozzle was cleaned with the ozone water, the number of defectswas reduced. From these results, it has been confirmed that the cleaningof the developing solution supply nozzle 304 by the ozone water is veryeffective.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

1. A developing method of developing a photo-sensitive resist film inwhich a desired pattern is exposed, comprising: subjecting the exposedphotosensitive resist film to a first developing treatment; supplying acleaning solution having an oxidizing property or alkalinity withrespect to the surface of the resist film to the photosensitive resistfilm subject to the first developing treatment to perform a firstcleaning treatment; subjecting the photosensitive resist film subjectedto the first cleaning treatment to a second developing treatment; andsubjecting the photosensitive resist film subjected to the seconddeveloping treatment to a second cleaning treatment.
 2. The developingmethod according to claim 1, further comprising: supplying at least oneof an ozone water, oxygen water, nitric acid, and oxygenated water asthe cleaning solution having the oxidizing property to thephotosensitive resist film.
 3. The developing method according to claim1, further comprising: supplying at least one of an ozone water, oxygenwater, hydrogen water, carbonated water, weak alkali water, slightlyacidic water, and pure water to the photosensitive resist film at asecond cleaning treatment time.
 4. The developing method according toclaim 2, further comprising: supplying a pure water to thephotosensitive resist film surface; and subsequently supplying thecleaning solution at a first cleaning treatment time.
 5. The developingmethod according to claim 1, wherein the developing solution for use inat least one treatment time of the first and second developingtreatments is an alkali aqueous solution in which oxidizing gasmolecules are dissolved.
 6. The developing method according to claim 1,wherein the developing solution for use in at least one treatment timeof the first and second developing treatments is an alkali aqueoussolution in which reducing gas molecules are dissolved.
 7. Thedeveloping method according to claim 1, further comprising: supplyingthe cleaning solution to the photosensitive resist film to perform thefirst cleaning treatment in an off time in which the developing solutionsubstantially reaches the bottom surface of the region of thephotosensitive resist film soluble to the developing solution.
 8. Thedeveloping method according to claim 7, wherein the off time is obtainedby allowing a light having a specific wavelength to be incident upon thephotosensitive resist film during the development, and measuring a pointin which an intensity change of a reflected light from thephotosensitive resist film changes to a waveform indicating a monotonouschange from an interference waveform.
 9. The developing method accordingto claim 7, wherein the off time is obtained by developing thephotosensitive resist film in a plurality of developing times, andevaluating a pattern after the development.
 10. The developing methodaccording to claim 1, further comprising: performing the seconddeveloping treatment after drying the surface of the substrate after thefirst cleaning treatment.
 11. The developing method according to claim1, further comprising: performing the second developing treatment in astate in which the cleaning solution for use in the first cleaningtreatment is left on the photosensitive resist film.
 12. The developingmethod according to claim 1, further comprising: performing apretreatment to supply a solution having an oxidizing function withrespect to the photosensitive resist film to the resist film surfacebefore performing the first developing treatment.
 13. The developingmethod according to claim 1, wherein the first and second developingtreatments comprise: discharging a developing solution to thephotosensitive resist film from a developing solution discharge nozzlehaving a discharge port whose length in a longitudinal direction islonger than a diameter of the substrate; and moving the substrate anddeveloping solution discharge nozzle from one end to the other end ofthe substrate with respect to each other to form a developing solutionfilm in the surface of the photosensitive resist film.
 14. Thedeveloping method according to claim 1, wherein the second cleaningtreatment comprises: continuously discharging the cleaning solution tothe substrate from a discharge region disposed in a nozzle while movingthe nozzle and substrate with respect to each other in one direction,wherein the length of the direction crossing at right angles to thedirection of the discharge region is equal to or more than a maximumdiameter or longest side of the substrate, and the nozzle continuouslyspouts a gas to the substrate from a jet region, and the length of thedirection crossing at right angles to the direction of the jet region isequal to or more than the maximum diameter or longest side of thesubstrate.